Whether or not they are exclusives, they are nothing more than cross-gen titles. Just because they are not available on the ps4, doesn't mean to say that they would not play or the development started on the ps4 before being bumped to ps5.
It is given that they will make use of the SSD, as that is what the ps5 has in it. To what extent like you said is irrelevant. At the end of the day, do people want gimmicks or "world transitions" in every game? Are they needed?
Like I said, don't think for one minute that we will be getting all the "new tech" just because it is on the ps5 or XsX. Apart from guaranteed faster loading and a few extra bells and whistles. At the end of the day, even the launch games on the XsX will still benefit from some of "new tech" even though they are releasing on the xbones. A bit of RT here and some faster loading there with a res and grfx bump for both consoles (ps5 and XsX) will be the extent of our upgrades until the games that really targeted the new consoles get made... Which ain't happening yet.
The people running around proclaiming cross-gen bad every 5 minutes sound like they have either never witnessed a new gen or are just simply swallowing the company PR bullshit. Unless of course, sony devs are somehow capable of knocking out their AAA titles in 18 months all of sudden... We will see.