This is how console generations work. Consoles are closed box fixed hardware and as the generation progresses developers only have that spec to work with so they use more and more tricks to squeeze everything they can out of those fixed specs. Some of the best looking PS3 games for example came out towards the end of that generation as developers got all they could out of that.The games are already being built and downgraded to ps4. Nothing will change on that front. High end enthusiast hardware has always existed.
Ps360 games didn't suddenly go down in quality when X1 and Ps4 came out.
You're naive as hell if you think half way into a generation an console with a decent amount more power doesn't change things. People won't still get the quality of games they would have gotten anyway. Maybe developers will pull the same stuff they do on Xbox One and simply lower the resolution but still target the higher end PS4 or even worse.
There's reasons for people to be cynical. Have you seen the crap companies pull in this industry? Knowingly putting out broken and sub-par games with the attitude of people will buy it anyway or we'll fix it later with a patch and worse. Game companies don't do anything to instill the level of confidence you have that things will he hunky dory and nothing will change.
I get that some of you want this. Hell I want it but at the same time I recognize that it's bad for the industry as a whole. It's like this. Rich people don't wanna pay taxes but if none of them payed any taxes there would be collateral damage. The existence of a PS4.5 brings some collateral damage whether or not you wanna admit it.