The '90 Thalabert was one of those wines with the great combination of quality, price, and accessibility; and I went through like a case and a half in a year or two thinking I really should put some away, but never did. ('09 Lapierre was another one like that more recently that comes to mind.)
I haven’t had one for maybe five years, but based on how it tasted then, I’d guess well-stored bottles are still in great shape. FWIW, I also didn’t stock up on release.
Well stored bottles of 1990 Thalabert are still fine, rather perfectly mature (if not still a bit youthful) - in fact more perfectly mature than La chapelle itself (if not quite on the same level).