I think their strategy is to commoditize the Next.js and Gatsby differentiation; They host all JAM-stacks pretty equally. The add a lot of paid dynamic add-ons that are hard to do statically (and that they told you were BAD_THINGS at the start) like form processing and user management.

I think their model is more realistic as a superset of what Gatsby can offer, but I'm not convinced it justifies 100 million dollars of VC investment. BUT - I'm always off by a factor of 4x (projected costs, effort estimates) so if you think it's worth 25 million, then you should go for it!