Me. Despite the wired connection, I've occasionally encountered buffering with my high quality Linux ISOs in Infuse or Plex.
Maybe more memory could improve this, although surely there's a software issue somewhere that causes this.
The only time plex has been slow is right after one of their updates before they fix the bugs they always introduce. Faster hardware won’t fix that. Also apps need better preloading when scrolling. But again faster hardware isn’t the solution to sloppy devs.
Also I play back full 4k BR disk rips.
I run Jellyfin on my Windows tower with my 4K Linux ISOs streaming from a NAS. I had to fine-tune the files to direct stream to my Google TV box. I don't remember all the details but it involved lots of ffmpeg commands and downloading external subtitle files. Worth it to see every pore in Linus's face