One can try putting themselves sometimes in the position of an old person. Let's say you have a heavy steel rollator with grocery bags hanging from the handles. You've spent an hour going to the store in the summer heat and are quite exhausted. Now try to enter your building. There's locked door that needs to be held open, and two thresholds, one for the platform in front of the door and one for the door. You can't go over the first threshold with your rollator as that would prevent the door from being opened.

Now, I think the assumed way to get in is to keep the door open with your body while simultaneously lifting the rollator over both thresholds. This requires considerable strength, as you have to reach far with a heavy weight. Maybe an athlete could do it. Not an old exhausted person.

An old person needs to first leave the rollator out, open the door and make it so it stays open with a hook. Involves crouching and working with your hands close to the ground. Then lift the rollator one by one over the steps and go inside. Then come back out and close the door.

A foot operated door stopper and a few slopes could probably ease that up tremendously.