Forget about sex for a minute and think about junk mail. There are laws in some states that require your "affirmative consent" (that is the actual phrase used) before someone can mail you certain things - specifically stuff that is going to cost you money.
Did you just compare receiving unsolicited mail to rape?
I know you're not really equating them, just like I did not equate a woman's vagina with an unlocked car in other threads. I know it's an analogy.
There used to be a scam wherein a company would mail you some item you never ordered/requested, then bill you for it. They basically forced you to purchase some stuff you never wanted in the first place. They then moved to the "opt-out" model wherein you had to prove you said "no" in order to get out of paying for the unwanted, unasked for item. So then states passed laws which require "affirmative consent" from you before the company can bill you for an item they've sent you.
Of course, this absolutely makes sense.
As I see it, the California law is simply attempting to codify a similar "affirmative consent" position for college campuses. Everyone (I hope) agrees that just forcibly raping someone (or forcibly making them pay for junk they didnt oreder) is wrong. But the old "opt-out" -"she didn't say no" model isn't enough anymore either. People need to have actual affirmative consent before they do stuff with consequences to other people.
"She didn't say no" is not, and should never have been (if it ever was), sufficient to establish consent, nor is it sufficient to establish not-consent.
But I think your analogy as a basis for 'affirmative consent' fails for at least a couple of reasons:
i) Affirmative consent to purchase a product is almost certainly somehow defined. You signed an invoice with your credit card, or you put in you PIN, or you gave a verbal 'yes' over the phone, and the company recorded it. How can we find the analog for sex? I don't know what 'affirmative consent' for sex is, and no one can tell me. Not because they're being malicious, but because I suspect they don't know. The legislation doesn't tell me anything except to define it circularly and I have no idea how 'affirmative consent' differs from 'actual consent'.
ii) "Affirmative consent" requirements were not the only way to stop companies doing what they were doing. There's an even better way, I think. Simply prohibit companies from forcing payment out of people for unsolicited goods. If you can take ownership of any unsolicited goods sent to you without any obligation to pay, I can guarantee you companies will stop sending them.
iii) "Affirmative consent" requirements are not the right response to combating "she didn't say no=consent" equivocators. The correct response to anyone who thinks "she didn't say no=consent" is to point out that "she didn't say no", on its own, is not sufficient to establish consent nor to establish not-consent.
"Affirmative consent" is not some made-up phrase just for college sex. It is a legal concept that is also used in other situations like junk mail.
And companies can prove my affirmative consent (or fail to prove it if I didn't give it), because they'll have my signature on something, or a voice recording of me saying 'yes, I consent to changing my long distance carrier to company x'. It's clear to me what affirmative consent is in regards to a commercial transaction of that nature.
What's the analog for 'affirmative consent' for sex?