Absolute bollocks !
Yes, generally there are minerals in both "tap" (utility produced) and so called "spring" water (the term "bottled" could be either, as there are some legal complications with the term "spring" - it depends where you are).
Bottled water, generally, will have been sanitised using both UV and Ozone - pretty much most regions will have legally enforced testing requirements for a number of possible contaminants.
Now as far as RO water is concerned, there's no such thing as "type". The point of using a reverse osmosis filter is to reduce the dissolved particles (TDS*), which can range from natural "salts" (which would depend on the underlying geology of where the water was drawn from or type of land/rock that it's passed over or through to reach the area it's been drawn from) to added chems used for sanitisation/cleansing to make it suitable for human consumption.
You can usually get a "water report" from a utility provider, but also remember that utility water will probably contain traces of chlorine or chloramine, and possibly fluorides.....
Around here, the tap/utility water is between 400 and 750 ppm* TDS*, but it will vary as the break down of those numbers, would show the highest levels of calcium and magnesium salts - both of which contribute to "calcium hardness" in the water i.e. the "scale" found in domestic kettles is mostly chalk (the underlying geology of the area).
Hard water can create a certain level of "off flavours" (some just allude to this as tasting "home brewed" - yet there can be other reasons for that too), so the vast majority of beer breweries will, if they're not in a "soft" water area, treat their water to soften it. Some will just use stuff like salt, others will filter, even down as far as reverse osmosis.
If you are relying on the water minerals to have any real effect on your brews i.e. the yeast, it would have to have the nitrogen levels of raw sewage. That's not to say that some locations don't have some idea about apparently problems with water supplies i.e. areas of large scale agriculture can often show higher levels of NPK from surface run off and the nitrate count will increase over the natural.
If you want consistent results and a good level of control over how the yeast is likely to work correctly, RO water is fine as you would generally be providing all the nutritional needs of the yeast in the nutrients, energisers and other ingredients. Which is why you don't get a water report with complete break down to calculate out the tiny/imperceptible levels of minerals to factor in with the nutrients/energiser/etc etc.
Ideally, if you want the, apparently, best results, the water for brewing/mead making/etc should be as "soft" as is practical.
I use the RO water from the local aquarium supplier (less than 50 ppm* TDS*, usually about 20 ppm* TDS*). Yet I'm also working on a home RO plant, but as we're now on "metered" water, I'm thinking about rain water harvesting, so the RO plant would just be for removing any airbourne contaminants picked up.
It's also, apparently, good for watering orchids as it prevents the occasional "die off" that can happen if the orchid(s) are watered with tap water - the occasional die off, is, I understand, connected with the slow build up of chlorine type materials....
Oh, and for info, generally speaking, utility water is generally, much "cleaner" than bottled or spring water (you can confirm that with water reports from your utility provider and then from the spring/bottled water provider. And don't believe all the marketing bollocks that the spring/bottled water providers want you to - they're just in it to sell more bottled water). If you looked up the info from "Thames Water", you will find a number of apparently "official" reports that say about the water in London being extracted from the Thames (among other places), that has been treated, pumped, used, recycled/treated and returned to the environment up to 7 times. I have no idea how someone worked that out, or even whether it's true or not. All I know is that London tap water, like the rest of the South Eastern corner of the UK, has high calcium a.k.a. Chalk levels as that's the underlying geology of the area. Take a tap sample and it will prove cleaner than anything in a bottle from a supermarket, irrespective of idyllic marketing of French Volcanic rocks, or Scottish mountains etc. That really is bollocks!
And while I don't work directly in the world of water treatment, I've been working around it for 15 years on and off. Enough to learn what seems to be best for both my home brews and the aquarium fish (and "erindoors" orchids).....
ppm* = parts per million
TDS* = total dissolved solids
Within the EU, for bottled water to be called "Spring" water legally, it must be bottled at source. If it's tankered from the source to a bottling plant, it can only be called "Bottled" or "Fresh Bottled" - and it must have a useby date code. You think it's clean etc, but leave a whole, sealed bottle in sunlight for a couple of weeks and you'll see it start to grow green algae. It will happen with tap water too, but generally much slower, unless your utility water tests positive for higher levels of nitrates - blame the agri' industry for that.
Now of course, don't take my word for it. You should be able to collect all the relevant data for your area about water quality, whether it's bottled water or tap/utility water. I don't know about how often you might need to have your supply tested in the US if you use water from a well. I believe that there are legal standards for "water owners" in the UK (possibly the whole EU) to periodically test. Whether it's the utility for a given area, or the Environment Agency, I don't know. I do know that you can't just chuck a pipe into a river or stream and pump it out, you have to have a license to extract.
Take my info with "a pinch of salt", but I'd guess that if you look into it, you'll find my reasoning is correct, with just the details being different for your area.
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