We use a data vault architecture as the raw/semi-structured source for a 'traditional' data warehouse built on Snowflake. Data vault gives more advanced users access to the raw data and Snowflake gives us all the scalability we need in terms of data volume. Will of course depend on the data model in your data warehouse but works well for us.
I am in a similar role and have the exact same opinion. Most vendors lack flexibility, can have significant costs even for small teams, and, at the end of the day, an in-house built solution isn't that difficult.
I think it's going to be a tough road to build a sustainable business in this space.