15-20 years ago

Having recently done a Firefly rewatch and going through Stargate Atlantis it is quite jarring to see Jewel like this but as you point out it's been almost 2 whole decades since then.

This is part of the "problem" with watching and rewatching shows that aren't quite yet old but enough time has passed for the actors to have visibly changed. Hell, RDA was already 50+ years old when he started the first season of SG-1 and was probably playing a character a good 10+ years younger if not 20.