It's very true. The click isn't the problem, the "waiting for transition between pages" is the problem.

Type username/password = ~1s each

Single keypress = ~0.1s each

Page load = ~2s

Before: username + tab + password + enter = 1 + 0.1 + 1 + 0.1 + 2 = ~2.2s

After: username + enter + page load + password + enter = 1 + 0.1 + 2 + 1 + 0.1 + 2 = ~4.2s

Roughly doubling the amount of time it takes to enter your information is significant and annoying.

Except it doesn't even take a second for the password input to appear. Where are you getting those numbers from anyway? When I tried it, it only took about 152 ms for all the data to load after submitting the e-mail address.

It depends greatly on your location, connection and browser. Many users are stuck on low quality internet connections or mobile devices where things can easily take a full second or more.