I wouldn’t say for years. It was still pretty much active in Shadowlands. It really became redundant when they introduced the solo queues in Dragon Flight 10.0 then RBG’s declined rapidly and now seem to be non existent.
Blitz can pretty much be explained by Forest Gumps’ Life is a box of chocolates. You just need to hope you get a good comp with decent players that understand what is required. There is also nothing stopping harcore pvp’ers from creating their own 10/15 man groups. It is just nobody want to take the time to wait while putting a group together if you can be auto queued.
im of the opinion that blitz is great content and that its brought back bgs/rbgs. sure it can be improved alot but its nonetheless great content so no,
it should not be deleted.
some classes are simply better then others in making plays of their own and some healers are simply better then others and in the right hands make a big difference especially the healers. thats just how it is (current version of the game).
whatever the class though its about learning the maps and read the plays and just improve and suck up your losses,
that has nothing to do with the gamemode itself wich is great.
old rbgs is still here for anyone who wants to play them. theyre not played now or before for a reason (most likely because of the reasons you mention about how and why rbgs was played).
Blitz is not wrong in its core. Thats just stupid. Blitz is great content,
IMO.