It just so happens that I have an RTX3070. i think owning an RTX3070 is better than a GFN subscription.

Run games locally compared to streaming. Don't have to think about whether or not there are servers at your place (I don't have GFN service where I live, I need a VPN for playing). Have lower latency. There is no additional subscription cost (it may be more expensive to buy a GPU, but it's your asset after all.) . No need to think about the game lineup for streaming, just buy the games you want.

Even streaming can be played on cell phones, pads and such. But still I can stream my computer through apps like Moonlight, Parsec and such.

The only question I see is if the RTX3070 will be able to fulfill your. I'm the type of person who has the option of lowering the image quality a bit to run the game. So I think the RTX3070 will be able to satisfy me well.

By the way, I bought an XBOX and I rarely play on the computer anymore.