I wouldn't go as far as saying it's 'dying' but I'm sure it's quite a bit different than you remember.
Basically the servers top heavy so leveling new characters can be rough but generally if you stick to the popular leveling paths, or send people tells around your level, you can still find folks. With you having most of your characters 45+ I don't think you'll have too much trouble.
Most would suggest finding a guild and thats a good idea if you wanna raid and such but I've flown without a guild for 10ish years and have had tons of fun and adventures even without one.
I should mention to you that Project Quarm just launched like a month back if you're looking for a fresh start or a higher populated server.
Regardless welcome back!
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*Blue Server/Retired*
ROGUE 60
SHAMAN 55
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Farewell!
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