I think the other part of this is that for these people (and probably most people) losing access to your gmail account is a catastrophic event. That access can

I think the other part of this is that for these people (and probably most people) losing access to your gmail account is a catastrophic event. That access can be lost because of an attack or by losing the keys. The former is actually much less likely than the latter so mitigating in favor of it instead doesn't make sense in this threat model.