I didn't say internet search was optional. I said Kagi was optional.

… implication of my comment was: “Which search engine may I use that doesn't indirectly cause harm?”

You're asking a question they aren't. They take issue with the specific spending of money on Yandex. So the question is "which search engine isn't spending money on Yandex"

No, the initial comment did also reference China, which Google and Microsoft are also in bed with... albeit to a much less degree then Apple.

Hence he's on point, as ddg ultimately uses bing under the hood, pretty much all search engines would be out.

A plausible argument could be that you're only using it, not actively giving them money (at least for Google/MS). It'd still call that hypocrisy though, if someone made such an argument.