What are the reasons why you are currently playing games on PC instead of consoles?
I live in Israel where physical games used to be really expensive at launch and kept their high price for the most part. Things are different now but I got used to playing on PC, last upgraded my PC in 2014 even tho I had a PS3 at the time, I always had to order games from overseas so that was a drag and something I did mostly for exclusives or games that weren't available on PC, or games that had crappy performance on the PS3.
I have a PS4 and a Switch and have a lot of games mostly for my PS4, but I still spend more time playing on PC. I prefer having physical copies for my consoles so even though there's more options than last-gen in that regard, it's less of a thing for me.
I think there will be a lot of people on midrange hardware that will jump into streaming, but not exclusively. The person with a 1060 might want to play Control or Metro Exodus on streaming where they can get improved performance, but would I think largely stay native for esports titles, casual games, and indies.
Upgrades can be pricey but it all goes back to the mindset of what you're buying into. If you want something that will simply play new games, it might not be worth it to you to buy a $400-700 gpu. If you want something that offers a lot more options for tuning your machine and getting high performance, it might be.
This is likely very true.
I'm mostly speaking of hardware-demanding games and less about games like Fortnite, Dota and LoL.
For example, my current rig is a i7-4790k/GTX 970/16GB RAM and newer stuff like Control (which I would love to play but have yet to purchase) would require some heavy compromises to run well on my rig. Metro Exodus did not run very well either, and I'm sure there's plenty of other examples.
Upgrading would most likely require me to buy a new CPU in addition to the GPU, which means I also have to buy a new motherboard. That means I have to buy new memory (correct me if I'm wrong).
That alone is probably more than a $1000 in my local currency, and it doesn't take into account a 4k monitor to accompany a GPU able to output at that resolution.
If you told me I had to choose between spending all that money or streaming Control from the cloud (and I am talking about a good and viable solution), you know which one I'm going to pick..