According to multiple debian based and ubuntu based and Arch I use. No. Not default. Cubic still is.
My experience was that some days ago I was trying to make my UDP faster, but turned out found out about BBR - for TCP. Well, lucky me - currently some country away from home for family reason. Plex generally takes 40-80s to start a movie/episode for me. And measly about 10s max buffer available - and this is on a 3-5Mbps show.
After BBR (note I have to apply on Proxmox host, my container are unprivileged and can’t set this themselves), I got 8-30s max to start a show/movie. And now comfortably sit between some good minutes on buffer. 15-20Mbps quality now playable.
To me personally it was black magic, and I was tossing it in just 2 days ago too
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Try Bottles! Available as flatpak so as long as you don’y have hate for flatpak, Bottles is there. All the normal flatpak benefit + a pretty great UI.
Not sure to WC3 suppose to run, but SC1 I owned on Bnet and I can tell, it works well with just a standard b.net install button in Bottles. SC2, HotS, D2R, D3 and so on I own run just fine, and fast too