Mate, Klopp was labelled a cuo-final bottler for years before we finally won the CL
The only final I think he bottled was the Europa league one v Sevilla (if memory serves me).
But yeah, these narratives can be unfair, and CL and national cup KO ties at the very top are about the finest margins.
Maldini, who won 5 CL, was always "unlucky" for example for Italy (94 WC final, 98, 00 Euros). That sort of stuff doesn't taint my perception of a player/manager very much. Sure, Guardiola's stock has gone down in the list of top 5-10 managers ever, but he is still going to be in the spot unless something drastic happens like he can't make top 4 for years and years.