I think Patreon has better rates and now they have commerce.
Considering you'd only be paying Apple 15% (I doubt many people on Gumroad are making more than $1 million) it still seems like a relatively good deal in comparison.
The company that was (still is) eating Gumroad is Paddle that have true 5% + 50ยข pricing.
Gumroad, Lemon, Paddle all do digital files fulfilment. Paddle wont give you website just pay links / overlay. I guess thats main reason why some people choose Gumroad/Lemon over Paddle.
Yes, Paddle is also a competitor but my main point was that many people on social media thought Gumroad was too expensive yet it turns out no sellers in the real world actually cared. The benefits of Gumroad (apparently to them) outweigh the extra 5% they pay.