If the screen were on the top like a tablet instead of being a clamshell, and it had controls on the side, that wouldn't be much different from a Steam Deck in size. The picture is of a PS One, not PS1.
To be clear, I'm not talking about a literal PS5 Portable using an AMD APU. I mean any means possible using current technology to reach real performance equivalent to a PS5.
Suppose this hypothetical device used GDDR6. With a 192-bit memory bus and faster memory (18Gbps vs 14Gbps), we can close enough to PS5 bandwidth that the difference is negligible, and it would cost the power budget something like 20W. For a device like Super Switch that's an unholy power draw, but for something already drawing 70+ watts it's still ill-advised (which is why my original post didn't suppose it) but possible.
My argument is that the technology is there, if someone had the will and a few hundred million dollars to burn. I know that it's a bad idea, that it would be heavy and hot and have battery life that could be measured with an egg timer, but there's no physical or technological barrier to its existence today. And every year technology will improve a little here and there to make that battery life tolerable: more efficient memory, more efficient process nodes for the SoC. TSMC plans to lower power consumption vs N3E 40% by the second half of 2026, that's only two years away. LPDDR6 will be able to hit the same speeds as the memory PS5 uses, for less power. Samsung plans to commercialize energy dense solid-state batteries by 2027. Suddenly in just three years our battery life can go from 55m to 2.5h.
Even in 2027 it would be hot and expensive though, so I want to clarify for the third time that I do not think this is a good idea. PS5 isn't optimized for energy efficiency, and it's on a process node two generations old. I want to prove the point that while tech hasn't reached the point we can have a good handheld that powerful, we can have a bad one that powerful, and one that's 'okay' is foreseeable.