Now the question becomes whether it is worth spending time and effort learning more in terms of design patterns, DDD (maybe even CQRS and Event Sourcing) and specifics of these large third-party frameworks as well as practicing working with all that with a benefit of developing really solid enterprise-ready SaaS platform from the start VERSUS moving much faster by developing a more lightweight MVP in Python/FastAPI stack (with PostgreSQL / GraphQL / Vue in both cases) - still with basic/core enterprise features like cloud-native scalability (using Docker swarm mode) and multi-tenancy (using PostgreSQL row-level security) - with a disadvantage of having somewhat less solid architecture and/or some technical debt initially.
There's a lot to enterprise stuff that also has nothing to do with the tech [1] so I would recommend starting with the default asp.net templates and build from there. Move fast and then add in the enterprise specific patterns when you need it.
But nothing I say will be as useful as just working with it. Try spending a few hours working with some of the bigger frameworks and I'm sure you'll get it pretty quick. If you need help then there are plenty of people to ask as well, from HN to twitter to the .net repos.