At least it is better to say that it 'could have' been said by Banda Singh Bahadur rather than Guru Gobind Singh.
Yes, I would agree with you on that. And it sounds more like something that Banda Singh would have said. Actually I like the quote no matter who said it. This however is always the problem with "what Guru Gobind said." I am not quarreling with you, just noting the difficulty of pinning down authenticity for anything related to Dasam Patshah. It is troublesome.