I wrote what I wrote in an unclear way:
"you're not correct about Spamhaus and being forced to use Google / Apple"
What I meant is that you weren't necessarily correct about Spamhaus, nor correct about being forced to use Google / Apple (which I thought was a reference to the fact that 98% of the world use Google's browsers and Gmail and/or Apple's Safari and/or Mail).
I see now you were referring to using a mainstream browser to communicate with Spamhaus. Yes, that's uncool. And yes, I wholly agree that the email address to request unblocking should not be filtered like it is.
Sometimes we worry so much about the symptom that we forget about the problem. Perhaps it'd be worthwhile to just ask someone else to forward an email requesting removal to Spamhaus' removal address.