Have you tried sunshine + moonlight? I've heard it has lower latency and better streaming quality.
Steam streaming is more convenient if the game is on steam and it's turn based or something like that. Also if the (mac) box you're streaming to has multiple monitors, Steam will continue to show the game if you cmd-tab out of it, while moonlight will minimize from the start.
Especially now that they added a 4:4:4 chroma subsampling option which fixes things like text edges in some cases.
Anything more than that and the value proposition goes way down. For every 50 grams lighter I am willing to lose 1fps. For every fan removed I will drop an entire resolution (4k -> 2k -> FHD...) Change "lighter" to heavier if it makes sense. My comfort and aesthetic matters more than competition quality, pixel perfect yadda
I keep starring these remote display projects but none have convinced me to provision a client machine for the purpose yet.
I've run Moonlight on a bunch of things from my TV, crappy old Android TV box, phone, tablet, laptop, desktop, ROG Ally; don't recall if I ever tried a Pi, but I might give it a go.
My advice is, whatever you use, make sure it has wired ethernet for a consistent experience. That said, a more powerful device on the receiving end (Moonlight) with good high-speed wifi should also work fine, but almost always try to keep the PC end (Sunshine) hard-wired.
I got some hardware, someone else mentioned h264/265 hard requirements, but there were codecs before that for FHD that even a pi model B could handle (among them x264 i imagine). My main viewscreen is 720p60, DLP, it's real sensitive to artifacts in the visual output being literally glaring. doesn't take much horsepower to move 720p60 relative to fhd or 4k, imo; but here i am, hands out, begging for solutions!
In terms of codecs, Pi4 is the best option (out of the Pi family) for hardware video decoders, Pi5 removed some hardware decoders which is unfortunate.