FFXIV raiding is a series of DPS checks. Yes, every single raid at its core is a DPS check in FFXIV with interspersed mechanics, either due to an enrage or things much more specific/tangible per a part of the fight. A1 and A2 are mostly extremely easy enrages, though not easy enough - players to this day still wipe on them.
A3S, there are two very specific DPS checks, arguably more depending on overall gear/skill but there are two very big DPS checks, Hand of Pain and when a Limb grabs your healers. When learning Hand of Pain in i190, we had to push out quite a bit of DPS, we HAD to look at our parsers, at the damage incoming tab, and see who the heck was slacking, what CDs we could throttle from X point without being a risk to overall enrage, see how much damage a class could do in the 20s the Hand was active. Heck, when battling the enrage we had to look at what a class is doing at X point because we could know who was slacking - that enrage didn't come for free in near i190. That enrage still doesn't come for free for most groups in i200.
Same with A4S except the DPS checks are even more sensitive overall when it comes to push timing. Someone slacking? You bet we rode them until we could clear, like any good group will do, because we don't want slackers wasting all of our time after a few hundred pulls. The other night on A4S we enraged a bit earlier than we normally have allowance for and I got called out for being 100 DPS lower than I should have, and I sucked it up and realized what I did at a certain point was simply no good. I used that info to get better.
Not to mention countless times we've wiped and looked into the healing/tanking side of things and found out what wiped us, who was slacking with CDs, and how to fix that with new CD timelines or an altered strat.
It seems like you're pro parser (I guess?), but you believe that info shouldn't be given to others unless they want it. Sorry, can't get behind that, DPS is too big a deal in FFXIV. If you suck as a DPS, much like sucking at surviving as a tank or healing as a healer, tough cookie, everyone should know who to blame when you wipe because maybe for once you'll do some research and not get carried, or get laughed out of a group for being unwilling to improve.