Wyeast 2565 occupies the same Kölsch niche as White Labs WLP029 — an ale strain fermented at moderate temperatures and then given genuinely lager-like cold conditioning afterward to develop the clean, crisp character the style is known for, rather than a strain that's cold-fermented from the start the way a true lager would be.
At 72-76% attenuation, 2565's range overlaps closely with WLP029's 72-78%, and the two strains are close enough in practice that most brewers choose between them based on format (liquid vial versus liquid smack pack) and availability rather than any dramatic expected flavour difference. Both carry a touch of subtle fruitiness even at cool fermentation temperatures, a real trait that distinguishes an authentic Kölsch from a beer simply fermented with a genuine lager strain instead.
Altbier is the other common home for 2565, sharing Kölsch's general "ale fermentation, lager conditioning" approach despite reading maltier and darker as a finished beer. Skipping the extended cold-conditioning step is the most common reason a homebrewed Kölsch or altbier falls short of the style's expected clean, polished character, regardless of which specific strain — 2565 or WLP029 — actually did the fermenting work in a particular batch of either related style of German ale.