What you’re not considering are Dependencies and Partnerships.
It’s great when companies announce “Partnerships”, their marketing and legal teams spend ages wording contracts and press briefings that basically announce “We’re now joined at the hip!”.
What you may not realise, is that every time you choose to use a 3rd party tool you are tying yourself to that company, unlike a partnership the dependancy only goes one way (like the Marketing and Legal blurb).
What happens if they decide to cancel the product?
Or they change how it works, and suddenly it’s not compatible with how you are using it?
Or they double their yearly developer licence?
Here we use lots of open source tools, while there is only “community level support” and the ramp up time may be longer than for an off the shelf tool, we consider that worth the price we’re paying.
We are part of that community. If a version is released that breaks our software, we have choices, we can continue with the version we’re using, and choose to maintain that version our selves. Or we can participate in the project and patch the code so it will continue to work for us.
If the open source project falls by the way side, we’re still left with access to the source code, so we can continue to build and maintain that too if we wish.
We believe going open source gives us far more freedom than tying ourselves to other companies, who can (and do) change their pricing policies.
Cost-per-developer next year could be twice what it is this year. Changing to a different product could equally cost as much or more.
My two cents.