I need to buy one BA15D to replace a burned out Halogen 120V 75W garage
stair light that is attached to the side wall.

It doesn't need to be brightly lit as it's a short set of open steps and
it's not on a dimmer so I don't care about the wattage all that much.

But I was told by someone dimmable LEDs are more robust than non dimmable
LEDs.

Amazon has three kinds of 12V BA15D LEDs with respect to dimmability
[1] some don't say if they are dimmable
https://www.amazon.com/BA15D-Bayonet.../dp/B07GKCC76Q
[2] some say they're not dimmable
https://www.amazon.com/BA15D-AC100V-.../dp/B07RFFZ914
[3] some say they are dimmable
https://www.amazon.com/Equivalent-40.../dp/B08DP6CWNS

What makes an LED dimmable anyway? Is it just advertising hype?
Or does the electronics have something special I can actually see inside?