10 teams of 3 each owning their own little slice of the pie sounds like an organizational nightmare; mostly, you can't keep each team fully occupied with just that one service, that's not how it works. And any task that touches more than one microservice will involve a lot of overhead with teams coordinating.

While I do feel like one team should hold ownership of a service, they should also be working on others and be open to contributions - like the open source model.

Finally, going from a monolith to 10 services sounds like a bad. I'd get some metrics first, see what component of the monolith would benefit the most (in the overall application performance) from being extracted and (for example) rewritten in a more specialized language.

If you can't prove with numbers that you need to migrate to a microservices architecture (or: split up your application), then don't do it. If it's not about performance, you've got an organizational problem, and trying to solve it with a technical solution is not fixing the problem, only adding more.

IMO, etc.