To remove the jumpscares, we need to download UndertaleModTool to access and change the game files.

You can download UndertaleModTool here:
https://github.com/krzys-h/UndertaleModTool/releases/download/bleeding-edge/GUI-windows-latest-Release-isBundled-true-isSingleFile-true.zip


After you download UndertaleModTool, right click and extract the zip file.

Next, open the newly created "GUI-windows-latest-Release-isBundled-true-isSingleFile-true" and "windows-latest" folders. Finally, open "UndertaleModTool.exe"

When you open UndertaleModTool, you will be greeted with this. On the left you have the file tree and on the right you have the file viewer.

Go to file > open.

Next, navigate to your Pizza Tower folder. If you don't know where that is, you can find it by going to the steam library page, clicking the gear, and going to Manage > Browse local files.

Finally, you're going to open the "data.win" file. (Note: Just to be safe, create a copy of the file as I did)

In the search bar, type "gml_Object_obj_monster_Collision_obj_player"

On the file tree, open Data > Code > gml_Object_obj_monster_Collision_obj_player
This is the code that activates the jumpscare.

On the right side, you should see the code.

Scroll down to line 64. This should have the line "fmod_event_one_shot("event:/sfx/enemies/jumpscare")."
Select that line:
And replace it with: (copy and paste)
That's it.

Now that the deed is done, you must save your changes.

Close UndertaleModTool. A dialog box will appear to confirm the exit. Click yes.

Another dialog box will appear to save, obviously click yes too.
When the save window appears, replace the file "data.win" in your Pizza Tower folder.

Make sure you confirm that you want to replace the file.

After it finishes saving and successfully closes, you can now play Pizza Tower without the jumpscares in Don't Make A Sound!

If you want, you can remove UndertaleModTool.

Video of it in action:

I will likely remove this guide if there's ever an official update that does this.