No, streaming was free. You only had to pay for the games you wanted to stream (either by buying them or for the selected games in the Pro subscription).

I thought the 4k streaming or upgraded streaming costs money?  

Just looked, it was $10 a month for surround and 4k....  plus buying games....  it was a dumb idea.  Charging for streaming and charging for games is just too much.  

Indeed no need to quit, my physical backlog will keep me busy until I can't hold a controller any longer .I won't buy any console without physical media. I use them to watch (4k) blu-ray / dvd, remove half their use is no more use to me. I do buy digital games though, not opposed to them as long as you can download them. Especially for VR, swapping disks is not convenient. Yet for big AAA games, a fancy steel book edition >>> digital download.

I still have that with movie streaming, it's like watching you tube instead of a real movie. I'm a stickler for 24p for my movies and most streaming apps butcher it to 60hz with compression artifacts in busy scenes. That judder from 24 to 60 is annoying. Plus every streaming app has its own sound and subtitle (non)options. One uses Dolby Digital, some support Dolby Atmos, Disney+ uses Dolby Digital+ is a way that makes my amp crash :/ (had to downgrade it to Dolby Pro-Logic 2 over PCM). Nothing like blu-ray where DTS-HD MA and Dolby TrueHD deliver lossless compressed surround sound.

Steam is a bit of a rip off btw. I used to be able to buy one physical addition and play it with up to 3 friends in LAN. Now you need 4 copies of the digital game to do the same. On console you can still buy one digital copy to play together on one online account. (2 boxes). At least Steam lets me share my games with my kids nowadays, although we can't play the same game together.

4K streaming is optional.

If you want higher resolution / better image quality for your hardware at home, you also have to pay more to play the same games (One-X-enhanced instead of One-S settings, PS4-Pro-settings instead of PS4-settings, Series-X-settings instead of Series-S- or One-X-settings, PS5-settings instead of PS4-Pro-settings, more expensive PC-graphic cards...) 

Sure, but stereo is kind of ridiculous.  I mean the Wii U has 5.1 PCM output.  Either way, I stand by my opinion.  Stadia, for me, was silly and DoA.  $10 a month for 4k and surround...  and having to buy games.  But you are entitled to yours.

Edit

Surround always has and always will be important to me.  Really adds to the atmosphere.  

I prefer physical because I actually like to own my media. I never owned an mp3 player, never had an account for iTunes, Spotify, etc., and never bought a digital copy of a movie. I still buy CDs (too many to count), Blu-rays (nearly 100 movies so far), print books (mostly manga), and so far I own 60 different games on physical between the PS4, PS5, Xbox One, Series X, and Switch, to say nothing of the dozens I have on older systems. I did download a few Virtual Console & WiiWare games on the Wii & Wii U, and I did download Blaster Master Zero on the Switch to have something to play at launch besides BotW, but aside from that every digital game I've downloaded I got for free as part of some promotion. I do have Game Pass, but I treat that as a "try before you buy" sort of thing. If I like the game, I buy it physically if that's an option.

If the option to buy physical is taken away from me, then I'm done supporting the video games industry. I'll have several decades worth of games at my disposal to last me the rest of my life. I'm not sinking hundreds of dollars into something I don't even own.

Just 3 more months Stadia chan :(

Surprisingly... October brought new games to Stadia and into the Pro subscription, including the beforementioned Tangle Tower. So for three and a half month the release for Stadia will show fruits. :)