Re: Even if an iPhone . . .
The PS/2 used different I/O cards. MCA. It never had an open BIOS. Nor did the PC/XT/AT.
The compatibles of the PC non-PS/2 systems didn't have an Open BIOS either. Compaq developed their own and the Phoenix BIOS a commercial clone supposedly created by a separate team reverse engineering the IBM PC BIOS (not PS/2) and issuing a spec. It was licenced. It was never open source at the time.
The IBM PS/2 was really the third generation IBM-PC. Unlike the first which used catalogue HW, IBM proprietary BIOS and MS's version of a reverse engineered CP/M-86, it had more proprietary HW and more IBM designing in it.
"These models were in the strange position of being incompatible with the IBM-compatible hardware standards previously established by IBM and adopted in the PC industry. "
The higher spec models were supposed to run OS/2, incompatible with DOS. The lower spec models were inferior spec to PC-AT clones at the same price, so despite about 3M corporate sales, the PS/2 was a failure. The PCjr even more so outside the USA.
No PS/2 models could take the popular ISA expansion cards.
Ironically the PS/2 came out the same year as the Archimedes running on ARM. 1987.
PS/2 and OS/2 were too little, a couple of years too late.