From the POV of an indie dev selling closed-source binaries, would a source-available license gain any goodwill in this space? And how would you tackle pricing?
That being said, I highly value having access to the source code, even under a restrictive license. The source code is the best documentation, it doesn't lie. Also being able to make small changes, recompile with different libraries, etc... but for me, the "documentation" aspect is the most important. I don't do security, but I guess being able to audit the code is a good thing too.
For me, open source goes beyond the "freedom" aspect. Also, AFAIK, most commercial game engines are "source available" too.
Other nice thing about BSL is it converts to an Open Source license after 3-4 years which addresses the concern “what if the software vendor goes out of business”. You can support it yourself or another vendor can pick it up and support it after that time period.