All the podcasts I listen to still ask for donations to help keep the lights on, it became easier now that most of them have started using patreon.com. I would much rather donate than listen to adverts because I think podcasts are kinda personal, sometime I think of it like an old friendship. It's nice hearing from the podcaster every now and then, I like to hear about their lives intertwined into their podcast, sometimes over months, but an advert just breaks the illusion. If my podcasts start getting spammed with adverts I will definitely be unsubscribing.
I think most niche podcasts are still going to struggle to make a profit from their work.