[JohnStrangeII]

It will substantially harm sales of B2C products, but it may make sense for B2B products that require support and training and aren't based on any substantial know how/trade secrets. In that case releasing as open source might even be beneficial. A good trade off is to release libraries as open source but keep parts of your final product (e.g. GUI) proprietary.

Even in the B2B market successful open source companies often use dual licenses and release the open source version as a sort of crippleware by keeping essential libraries and tools proprietary or under very restrictive open source licenses.

[fr2null]

I think Kong* does this rather well. They have a usable open source product that has a lot of the core functionality and it more than enough for small businesses and hobbyists. They also provide enterprise support and a enterprise products which includes functions that are typically used by enterprises (like fine grained auth).

* https://konghq.com/