"Several years"?

Try "a decade and a half".

AT&T itself ported UNIX™ to the Intel 8086 in 1978:

https://www.nokia.com/bell-labs/about/dennis-m-ritchie/other...

The 8086 was the first ever microprocessor to run Unix – before 68000 or anything.

The first release of MS, later SCO, Xenix was 1981.

https://www.abortretry.fail/p/the-history-of-xenix

It was later ported to the 8086 in 1983 and 80286 by 1985.

https://landley.net/history/mirror/unix/scohistory.html

So Unix was running some 4 years before IBM launched the PC and Xenix was on the market by 2 years after launch.

That was a full 8 years before Linus got Linux 0.01 out in 1991.

UNIX is a 1970s OS; x86 PC Unix was a commercial 1980s product; Linux is a 1990s thing.