anyone who can buy groceries can also donate.
That is not always true, especially for people outside of the US. It is much easier for me to send money from my country via crypto than via credit-card.
Otherwise, discussions are usually fruitful (for example what I wrote above), I do agree that some things are too insignificant to discuss, but I am not sure that this is one.
I agree with you that I have an agenda, two actually. One- I like synchthing I want to support it, and donating with crypto is ~about the only way I can do it. Two - I want bitcoin to succeed. I don’t see how those agendas contradict.
Again, I am not sure about the structural organization in synchthing, but are you the only person who decides? If yes, then I assume it will take a lot of time until you add this option. But if you are not the sole decision-maker, how can we get other opinions on the matter.