A PC from 11 years ago is likely running a spinning hard disk and running a 32-bit version of the OS, no?

I meant slightly more recent, like when Windows 10 was released. But no, my relatives have PCs from 2010 running 64-bit Windows that I upgraded to SSDs in the mid-2010‘s and that are still running perfectly fine. I myself was running a 2012 PC (with SSDs from the start) until last year, and the replacement isn’t that much faster. I’m also running a second PC from 2016 that doesn’t meet the Windows 11 requirements but would surely be fast enough beyond 2025.

I bought my first 64bit AMD CPU somewhere around 2001-2002 (at that time this premium turned out more or less useless). And as I mentioned, you may switch HDD to SSD to get very acceptable performance from even quite old computers.

Vista was released in 2007 and supported x86-64. The first x86-64 machines from AMD were released in 2003.

But did people typically run Vista 64-bit or the 32-bit version?

No data to back this us, but my intuition would be that other than government or big corporations, everyone buying a new machine with Windows installed would get the 64 bit version. And even then the uber-conservative government / corporate buyers wouldn't be rolling out Vista, they'd be sticking with XP.

I’ll ask some MS pals for some data.