My apologies if someone has asked this, but I must as myself.
BfA is lagzilla for me. I tried all of the tips blizz provided to help with this and thus far it’s still there. I don’t really raid or run dungeons anymore and occasionally do battlegrounds since the lag problem is less… noticeable.
So what do you think? Once Classic arrives, I’ll uninstall everything then only install Classic and hopefully I won’t have to deal with ridiculous latency issues…
right?
Latency? Is it your provider? Do you live outside of North America? And you do mean latency rather than FPS lag, right?
Have you tried customer service forums? Traceroute?
Yes, latency, not fps. And yes, I live outside of North America (which I always suspected might be an issue.)
I am really quite ignorant on these issues though.
I sent a ticket to blizz and they referred me to a lot of sources. I’ve tried most but have been unsuccessful.
I had pretty bad latency issues when I lived on a college campus, and as you might expect, it was due to bandwidth limitations and having my connection throttled. But it drove me crazy for a long time because it only happened in certain areas of the game, so it was hard to troubleshoot.
Anyway, I ended up posting in the customer service forum, and they were genuinely helpful. It’s been almost 10 years but 
I bet you could get better guidance there than here.
I can tell you I don’t think uninstalling the game will be much help. It’s most likely related to your service provider. You can also look into a quick fix called “Leatrix latency fix,” which might look daunting, but it’s a totally legitimate function that many people have used for many years. That’s up to you, though.
Technical support forum:
https://us.forums.blizzard.com/en/wow/c/support/technical-support
Try posting your issue there and see if you get some solutions to try.
I see. This is good to know. Thank you!