I understand the perspective and opinion, but I like to think about incentives and consequences.

What's Google's incentive to protect your privacy, and what are the consequences if they fail to?

Compared to a firm that is marketing services on the proposition of privacy being at the core, the risks to Google's business, reputation and finances are likely minimal.

Whereas, if one of the firms that markets providing services focused on your privacy is found to be intentionally and wilfully violating that, it ceases to be a violation of trust and becomes a violation of contract, false advertising... essentially fraud, and the consequences of deliberately misleading and defrauding customers is more significant than an accidental (or wilful) privacy breach by a corporation that openly markets itself as not respecting its users privacy.

You'd trust a company thats primary business model is based on the mass collection, analysis, and monetization of user data to protect your private data? Not saying I trust proton mail, but as far as I'm concerned Google is a malicious actor when it comes to my data same as Facebook, and I believe it's in individuals's best interest to limit their exposure

I trust the company who is under global regulatory scrutiny 24/7, and watched like hawks by every major news organization in the world for them to slip up.

If Protonmail fucks up, there's not going to be a NYT article about it.

Think about the different user bases and sources of revenue.

If google screws up, they might see a small blip in add revenue before recovering.

If Protonmail screws up, then they'll lose paying customers which is their only source (presumably) of revenue.

I can't say for sure, but I'd guess that Gmail has many more paying customers than protonmail. This feature exists specifically for those paying (enterprise/gsuite) customers.

Why trust either of them?