Mibu no ookami
Demoted Member® Pro™
That's precisely the point. For business strategies they're reserving the ability to do cloud streaming only for those who already have a PS5 but on that platform the feature is partially useless/redundant while the service is not available where it makes sense (PC, Portal).
Why streaming isn't available on the Portal today when there is obviously no technical barrier to do so?
There might not be a technical barrier, but they haven't done sufficient testing on the device. They've only just enabled PS5 streaming on the PS5 itself.
With sufficient testing and across varied bandwidths they'll either enable it on Portal or they won't.
On a PS5 you're more likely to have a stable connection maybe even on ethernet, with Portal, they know people will be outside of their home wifi.