I don't know what's included in the subscription.
I pay $100/year for a Roll20 Pro subscription, but then I also buy the Roll20 version of some books. List price is the same as the hardcopies. I've been averaging a couple products a year, so figure another $100 for content. According to my Roll20 stats, I've averaged over 500 hours a year there since 2014, though that includes time that I'm "in the game" prepping for the next session. But still, maybe 50 cents an hour spent on my favorite hobby for the past 42 years, so it feels like a pretty good value. Oh, I do buy the occasional item from DMs Guild, but not often and the cost is negligible.
I could imagine myself paying $500/year for D&D, but I'd need more value out of it than what I have now (basically VTT, character builder, and content).