On top of the other comments about price, last i checked, it doesnt support higher than 5ghz which was the deal killer for me, i almost bought it, hell i almost backed the project on whatever funding platform they were using, then that was revealed and i just forgot about it.
I am using the “Chromecast with Google TV” connected to wifi via 5ghz and use mkv files from collection via Jellyfin. I used to transcode from the i7-8700u but larger files took too long to start playing (with quicksync and proper drivers and passthrough) and tried turning off transcode and surprising works fine without issues. Ive tried 15gb files without issues.
So i would suggest checking your set up to make sure not something configured wrong and if you use mkv files try turning off all transcode to see if it works better.