Yeah, both VServer and Virtuozzo were roughly contemporaneous with the initial Xen release (2001-ish?), and only a few months behind jails.

But Virtuozzo was hampered by being non-free - OpenVZ wasn't open sourced until 2-3 years later, by which time the damage had been done (but, of course, Xen headed in the opposite direction at roughly the same time!)

And Linux-VServer was held back by being focussed so directly at virtual hosting providers - it positioned itself against fcgi-suexec, fcgid, and php-fpm (and was much more unwieldy than any of them) rather than jails or VZ.

Both were more or less ignored until the late 2000s, by which time LXC had taken a lot of mindshare - allowing the "FreeBSD was years ahead with jails" meme to take root.