I had an XT. Not IBM. It had BASIC ROM. Everyone I know who had an XT (8088 or 8086) had BASIC in the ROM. None was IBM and all were different companies.

I don't think Compaq even made XTs, did they?

Actually (and I'm being pedantic here, I admit), only IBM made an XT, the others were all XT-clones or compatibles. And you could get a compatible ROM that contained BASIC. I also owned a non-IBM XT clone, which did not have BASIC in ROM.