Let me repeat what I already wrote since you seemed to have overlooked it (I really should have worded the first sentence differently by adding "Apple should no longer ask....":
Apple no longer asks users for the password of any macOS user account when repairing devices.
So unless Apple is trying to resolve a software or configuration issue, it is unlikely Apple will even boot the laptop to its internal SSD during a hardware repair unless the tech performs a clean install of macOS which would destroy all existing data on the internal SSD.
This policy is to prevent users from accusing Apple techs of looking at personal information or even keeping personal information for whatever nefarious reason, plus it is to protect the user's privacy. While this is Apple's policy, some techs may or may not follow it....so you are not required to provide any passwords to Apple (nor should you do so since passwords are very personal information). Without a password, how will the tech know what is on your laptop? The 2018+ Apple laptops have the data on their internal SSDs hardware encrypted all the time, so the only way to access any data on that laptop's internal SSD is by successfully authenticating with a macOS user account....that cannot be done if Apple is never given a password.
If you feel that Apple may think the issue is due to a software issue, then Apple may have you unlock the laptop so Apple can investigate possible software issues while you are there observing them, but other than that Apple won't be able to see anything on the laptop's internal SSD if the laptop is locked. If you feel this may happen and you are concerned about those apps, then delete those apps or perform a clean install of macOS.... Apple may insist upon a clean install anyway depending on the issue being investigated since that is usually one of the first things Apple likes to do unless a hardware issue is 100% certain such as cracked screen, etc.
You can always contact the local Apple service location which you will be using to find out if they will need to unlock your laptop and make a decision based on that and your concerns.