Phew thanks for all the input guys.
After reviewing all this I suspect my problem is two fold.
1: I'm just using the dinky router supplied to me by my ISP. It does well for TV/Movie streaming and various other things, but maybe 4k in-network streaming for gaming is just too much. It is a Wi-fi 6 router, but that's about all i know of it specs wise.
2: Distance. I'd say my PC is about 40-50 feet from the Wireless Router itself with at least 3 walls in the way. I get full wi-fi bars, due to an overpowered Wi-fi card I bought, but my tablet is less lucky when at the same distance. It gets about 2 or 3 bars out of 4 possible. It does fine for streaming anime at 1080p but maybe that's the limit.
It's still ok for playing VN's and other stuff this way. I was trying to play my Switch emulator (BotW) at 4k, and it just doesn't work out so well...
So you’re doing PC WiFi to router, then router to remote device via WiFi too?
Explains it.
At the very least you should put your dinky router into modem mode and use an aftermarket router.
I have a TP Link Deco mesh network, with all the nodes linked by Ethernet (currently power line - getting Cat6a lines installed soon). I personally recommend this setup, but it isn’t cheap.
Even getting a high end Powerline will serve you better than hoping to connect via WiFi both ways.
Sadly, home networking isn’t cheap.
My suggested solution:
The cheapest way to deal with this is to get your PC wired up via Ethernet to an access point and have your AP talk to your remote device.
Ideally the AP needs to be in the same room as your PC and remote device. It should also connect to your router via cable backhaul (hard cabled in or good Powerline).
That’ll decongest your WiFi as much as possible. When it comes to home networking, if you can use Ethernet you should.