Now when a user creates a pull request - last commit comment gets into PR Title's field. Since into PR further processing can be involved a broader community, that just developers, that last commit may not always be informative enough for all the people. Sometimes it is better to have a branch name as a default title for PR.

For some teams, for sure, last commit is a preferable solution.

Suggestion is to make a repository option for Default Pull Request Title:

-Last Commit
-Branch Name

Thank you,
Roman.