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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I think he mean on these new, modern ARM laptop. None has actually work well so far. This newer Qualcomm chips are those that they themselves put the effort in. Rest were few far and between - garbage from Qualcomm and rest is from community.