@aral I know this doesn't excuse, but.... sometimes there is an email address on the conference website (usually it says if a speaker has a question they can email) where you can tell them that a Google account is required on that form and if they want the widest variety of speakers they should not require someone to have a Google account.
I've sent that email a couple of times and got a positive response (and then they usually set it to not require an account).