Not wanting to "dirty the waters", but there I think there are two distinct areas here.

There is the fully blown, all singing, all dancing plugin with the well though out interface, version control, roadmap, etc... and then completely separate from that the "I've been working on something", developed a bit of code that might be useful to someone, format it into a plugin and put it out there - type plugin.

The first, obviously, takes a lot of work, effort and, frankly, is deserving of compensation.

The second, from my own personal experience, is part of the journey to the full blown plugin and is a rough and ready "do what you want with this" piece of code. I don't expect anything other than maybe a thank you and even better the price of a coffee in a donation, but I also don't intend to support it.
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