How long does white wine vinegar last if kept in a sealed bottle? Does this apply to the age of all vinegars kept in a sealed bottle?
For white vinegar: basically forever.
Vinegar is acidic, so most bacteria won't grow in it. Plain white vinegar in a sealed container will keep longer than you'll be around to use it.
Some vinegars (balsamic, wine vinegar, etc) can experience flavor changes & other undesirable effects when exposed to air, light, or extreme temperatures. Stored in a sealed container in a cool, dark place, they will keep for a very long time--but not always forever.