History in All Branches becomes difficult to see each time you merge from the develop branch to master

A branch (feature branch?) that creates some functional units from the develop branch is derived, and a pull request is thrown to the develop branch to merge.

When other developers' feature branches? are merged into development, each developer tries to make the lines as clean (and straight) as possible (sometimes merge instead of rebase) by rebasing the feature branches? under development to keep up with the latest development.

The develop branch is merged by throwing pull requests from develop to master at a stage where the develop branch is advanced to a certain extent (a stage where the development is well separated).

Then, when I looked at SourceTree and All Branches, the lines indicating the merge grew bigger and bigger like the picture. It's not particularly difficult to follow the history of each branch, but it's hard to see how all branches look in All Branches. Is there a way to keep the lines from swelling like this?