iOS 14.4.1 made the screen scrolling look choppy and laggy

Something installed is doing this

VPN

Ad Blocker with VPN

Anti virus etc

First try a forced restart

https://support.apple.com/guide/iphone/force-restart-iphone-iph8903c3ee6/ios

If that does not help the  next procedure would be to backup then restore your device to factory, and setup the device without restoring a backup, to see if the issue is replicated. 

Then restore the backup.

Here is a guide for those steps

Backup and restore

(1)How to back up your iPhone, iPad, and iPod touch – Apple Support

(2) Restore your iPhone, iPad, or iPod to factory settings – Apple Support

(3) Restore your iPhone, iPad, or iPod touch from a backup

Well if Apple is going to fix it, then it needs to be a problem that is determined a problem. I don't have any issues that you are talking about, I have all my phones that my family uses and my phone and work phone and none of them are having the issue that you are having. If it's a problem that you think you're seeing on more phones than one, then you should go to Apple Product Feedback and let them know that this is an issue you're having. If it's reported by enough people and determined to be an issue, then they will look into getting it corrected.

Not in my 14.4.1 phones.

If it has happened before it is a problem with your phone. Do you have at least 5GB empty memory?

Welcome 👍