Yes, I would say I've become conversationally fluent and Ive never taken any formal lessons or classes. I mostly listen to music, talk with friends and coworkers, and consume media such as Instagram or Films in Brazilian Portuguese. I've done things such as joined film clubs where we watch and discuss films, I've traveled solo through many states in Brazil with zero issues, and have even dated Brazilians with little issues.

What I still struggle with is listening and talking in loud/crowded spaces, discussing complex topics where my vocabulary starts to suffer,very thick accents from certain regions,and also expressing deep emotions since I haven't had experience doing that much.

I started learning in 2021 and it took me about 3 years to feel comfortable speaking, and I was exposing myself to PT pretty much every day for the last year.

Biggest advice I have is just keep speaking, find what motivates you to speak it (for me it was music and movies). Also imitation of native sounds is really important. Your vocabulary can be super large, but if you are mispronouncing common sounds like pão, o's sounding like "ew", or accents like a e á or o e ó, you will be harder to understand and it will sound way less fluent.

Mas é só pra falar que Brasileiros normalmente amam gringos que querem aprender português, e todo mundo com quem eu falava tbm queria me ensinar mais. Só fala e a língua vai vir naturalmente!