Maybe it will get better; I'm kinda of excited to ride the T extension in 2025.
Why? The T is an excellent case study in shittacular urban planning. The above ground T cut a vital link between BHVP and City College, fueled real estate speculation, and black flight. It doesn't go far enough (e.g. North Beach, Crissy Field) and the city has made it essentially impossible to extend. The extension is astronomically expensive and has been gimped ostensibly to save costs. What is being built are tiny platforms that can only support short trains, no express tracks, nada. There's zero room for expansion and it's basically going to be at capacity when it opens. The plan, last time I checked a loong time ago, was to gut the 30 and other surface routes to fund the underground operations so it's not like subway really represents additional capacity.
I assume you weren't around in 2007 when the T opened and shit hit the fan. Muni/SFMTA (whatever you want to call them these days) used all the new streetcars meant for T service to make up for abysmal dispatch reliability. Service along the other lines was an utter disaster. We're almost guaranteed to see similar problems in addition to whatever fresh hell beta testing the new subway infrastructure will bring.
But yeah the T is an embarrassment.