The majority of researchers use "edu" emails on their research publication, when some academia use Gmail as the corresponding address.

Many of the young researchers do not have a permanent "edu" email address. It is seem to be consensus of this site that Gmail is better than temporary emails and alumni emails. According to other answers, the Gmail option receive much more upvotes than the alumni option.

Established researchers and people on this site heavily promote Gmail; in contrast, on research papers, the vast majority of the junior researchers put their temporary institutional address rather than Gmail. Although I cannot find a research article backing up my "statistical findings", I am quite sure about this at least for students in my school.

In my opinion, alumni email combines the advantages of both Gmail (permanent) and institutional email (credible). However, people do use Gmail much more often than alumni email. I've read or skimmed thousands of papers and alumni address was noticed only once. I guess it might be weird if the email address and the affiliation come from different educational institutes?

So I ask: how is Gmail way better than the alumni email or temporary email? If Gmail is so good, why do people still use temporary emails at the most of the times? If I have a permanent alumni address, is it a choice better than my temporary address or Gmail address?