For me it works fine.
I just created a landing page with a little of SEO for each domain.
I've already sold one, about a month ago, a .bio, and every week, I receive at least 2 inquiries for new GTLDs, like .agency, .tools, .bio, .rocks...
I'm not in a rush to sell, so I reply with high counters.
If I find a well established website, for example, blabla.com, that deals with DNA, and I own DNA.blabla, or some agency's website, and I own blabla.agency, I contact them.
Usually they're very interested.
Bottom line, I am going to keep my favorit ones for a couple of years.
I think that's a great long term investment.