You have no facts. Just repeating Sony stan narratives
Cell is stronger than PS4 CPU= Bullshyt. You running with the koolaid Sony sold cause of that dumb ass decision to use the cell. It's "power" was woefully overblown by internet stans who needed something to grasp on to because of the PS3s price and it getting continually bested by the 360.
PS4 can't emulate Cell= Also bullshyt. Sony's justification for bullshyting people into purchasing games multiple times. If they wanted to, they could, and it's evident by the fact that random people on the internet have found a way to make it work, and you don't need a super powerful CPU. It might take some significant work cause how dumb the cell is, but it could be done if they wanted to.
PS4 can't emulate PS2=
A potato can emulate PS2
Basically some time during the PS3s life Sony decided they'd rather re-sell the old games instead of letting people just play them. Probably around the time they were looking into Gaiki
And they wove this web of narratives to deflect from what's happening.
Bottom line PS4 could emulate PS2/PS3 games if Sony wanted it to.
It's not the CPU. It's Sony's pockets preventing it from happening.