I don't understand the complaint, unless you're an exclusive X-box user and hate Playstation.
We played on Stadia, then it went away.
So we started looking into buying PCs.
Found Boosteroid and started playing there for $10/mo each.
Then found GFN was compatible and were thinking of switching.
Now we have the option to buy a PS5 and play split screen as we always wanted to. We'll still have to buy a new console, but we won't have to spend ~$3k on 2 new gaming PCs, or spend $20 - $40 / month for a service instead of hardware that we'll own.
So I don't understand the downside to also releasing on PS5, even if it's not coming to X-Box / Switch (yet?). If you only play on X-box or Switch, then you wouldn't be playing anyway, unless on GFN etc. So what is the problem?