per Google's onboard AI that's a holdover from an old version of Android. (I haven't had a Samsung in a while, so I have to take their word for it). You can turn it off in app settings.
I can say that the way Android's developers intend you to use it is to put the apps you use with semi frequency on your home screens in an arraignment that makes sense to you, and only swipe up to go to the full apps list occasionally for apps you don't use often, or have just added. From your description of use it sounds like you had been using the apps list the way the home screen is intended to be used. (moving stuff around so it's in an intuitive spot for you). I fully believe that Samsung's notoriously craptastic interface encouraged this for long after Android had moved on.
None of which helps you now that your phone does not work the way you liked. You may or may not find it worth switching over to user designed home screens rather than using the apps button. I only really started liking that set up when I started really using widgets. Large clocks and calendars for easy glancing at, smaller dual time clocks and weather, some apps that I use on the screen, others grouped by type in custom folders, streaming music control widgets, etc. Depending on how you use your phone, the juice might not be worth the squeeze.