Earlier quoted context omitted.
I'm less worried about GMail. It's much easier to start a GMail competitor today (in relative, not absolute, terms) than a Chrome or Android competitor, because of network effects. For example, Fastmail is tiny (comparatively speaking), and will probably stay tiny forever, but their service works fine, and there's no major obstacles (comparatively speaking) to replacing GMail with Fastmail for any of us personally.
Is it really? I think any potential competitors face many of the same pitfalls as, say, Chrome competitors do. Maybe even worse. Google slams its weight around when web standards are being designed so as to unilaterally benefit Chrome, but (at least in theory) it's a fundamentally cooperative process where everyone at least gets some sort of input to direct where each standard goes. In GMail's case, they can just arb…
Yes, of course it is. How many search competitors do you see out there? If you ignore resellers like ddg, these is bing, kangi, and country specific ones like Baidu. Email providers are a dime a dozen - Fastmail, Outlook, Protron, .. Google it, it's a long list. Hell. I run my own. I could not even contemplate building a web indexing engine.