GitHub stars are a useless metric. It’s basically a bookmark count. If there was any correlation between them and donations, my combined projects of 35k+ stars should make me at least a couple of bucks each month.
Instead, lifetime total of ~7 years is ~300 EUR, which includes donations to a NGO I forwarded, which account for most of it.
Most people will not pay voluntarily for something they can get for free. That’s just how it is.