Why passwords not restore Chrome

I started having trouble with my older MacBook Pro. It was extremely slow, took 45 minutes to start and sometimes would not start.

I thought there might be something wrong with my drive, so I erased it and re-installed MacOS. I even did the secure erase to write to all sectors.

I then used Migration Assistant to use my TimeMachine backup to restore my data, and it worked, mostly.

For Chrome, after the restore, it had saved my open windows, so when I launched Chrome, it opened all the windows that I had open previously.

This seems like it did the Chrome backup and restore correctly.

However, here’s the one thing that did not work:

It did not restore my logins and passwords. For Facebook, for Amazon, for gmail, etc.

I was using Chrome to save my passwords. I’m sure they were saved in Chrome, because I used Settings, and Autofill to look up a password recently, so they were saved in Chrome. I had stored my passwords locally, not in my gmail account. 

Can anyone tell me why Time Machine did not restore my passwords? OR

Can you tell me how to Restore my passwords?

I have an extra external drive, I could install MacOS on it and Restore again, if I could figure out the correct way to make it work.

Is Migration Assistant supposed to restore Chrome Passwords?

Is there any other way to get those passwords from my backup?

I had High Sierra on my computer previously, I installed Mojave when I re-installed.

Could that make a difference?

Why do passwords/user logins not get restored with Time Machine and Migration Assistant?

Or How do you restore them?

Thank you for any help!