Everything you say is true but I think the weights on your arguments are off.
A well funded adversary WILL take over your Google account. They'll do it by installing a keylogger and stealing your cookies, they'll do it because they know what signals the account recovery process is looking for - much better than you do, they'll do it because hacking you is far easier than hacking Google. (Two-factor authentication done properly, with printed backup codes in a safe location, can prevent hijacking most of the time.)
Second, Google accounts constantly do get hijacked every day. This draconian status quo might have been justified if it would prevent all hijackings, but it doesn't.
Third, my Google account is not my most important account. My bank account and portfolio which hold my life savings are arguably more important. But somehow I'm not worried at all about losing access to them.
Again, no system is perfect and it's mathematically impossible to identify the correct person for every account. But I still believe you can get the same false positive and false negative ratios without getting blog post after blog post from people who are completely stuck.