To get back to Classic for a bit, this is what I think is happening. Players who prefer the old ways (and full disclosure, I'd count myself among them, but to a smaller degree than most) complain/talk about the negative sides of modern WoW and Battle for Azeroth in general. While they do this they also talk about how things were better before and often mention Vanilla as a reference point. People who enjoy BfA now feel attacked by this and so they retaliate. Hence, liking Classic means you either have nostalgia goggles on or have no idea what you're talking about and will hate the same things you say you want 2 weeks after you start playing it. It's an amazing thing, where literally each side is doing to the other what they feel is being (wrongly) done to them. I feel like writing this is the most redundant thing I've ever done, and yet I also feel that it needs to be said, because it seems some people just don't get what they're doing, or at least I hope they don't (some do and are doing it on purpose but there's trolls everywhere so there's no point in even discussing them).
This is definitely why we do a beta test. We can also do things like reset the realm at a busy time like 4:30pm PDT to try and find the source of a certain issue where a crocolisk is losing it’s brain due to how multiple processes are interacting and mirroring code to form a cohesive world. There were similar types of issues like this back in 2004 but we wanted to try and resolve this one before the weekend for the folks who are testing. (Blue Tracker / Official Forums)
Only really to expand on Gráinne's comment as regards the 'collecting' and 'roster development' sections - which are, as said 'distinct' although they are intrinsically linked - I would like to point you in the direction of the in-game Achievements > Battle Pets > Collect tab. There are a series of achievements called Raiding With Leashes, pretty much all of which can be completed via the auction house - if you have the gold/inclination - or by completing old raids.