I agree with the parts worth engaging with. I hate when people weak-man arguments.

But interesting as this is, there are others who fit at least as well. That bit gold was the closest proposed scheme to Bitcoin is well known, and we know the proposer of bit gold (Szabo) was actively soliciting partners to help implement it as a real system right before Bitcoin appeared.

Also, people leave mailing lists and come back randomly months later all the time. Adam could have simply been unlucky, and busy with other projects at the time of the launch. Lots of people were, and kicked themselves for it (which honestly, it seems Adam did too!).

Adam Back is credited in the Bitcoin whitepaper as the inventor of Hashcash. W. Dai is credited as the inventor of b-money. But Nick Szabo is not credited as the inventor of bit gold, by far the most mature of these ideas floating around at the cipherpunks mailing list at the time. That's a conspicuous absence.