I don’t think the populace was tired of Thatcher.
The biggest cause behind her ouster was the European Union (then called the European Community), which she dared to criticize, and correctly.
I think she was done in by ambitious people in her own party who were tired of waiting for their turn. The same thing happened to Tony Blair. One reason why it should be two terms than out. You need to get out of the way, even if the people behind you aren’t of your stature.