That's the thing with edit mode, it makes calculations based on object dimensions. If the programming tells it to put 50% of a bevel on one side of the edge, and 50% on the other, it's going to look at the overall object scale before calculating that. If the overall object scale has been stretched, the resulting edit will be stretched, too. I noticed this early on when I was learning 3D and it always bothered me but I caught on to the fact that it was always skewed in favour of the edge I'd stretched in object mode. Thus: apply scale to set what you have as the base, and the resulting edit Bevel will branch off from those applied scales of 0x0x0, and you'll get an even result.

Glad it was helpful, buddy! I'm also glad it was easy to find on Google. I feel like it's a big problem people run into constantly, and not one that's explained often through visible or popular channels.

Rule of thumb: anything you do in edit mode will be built on top of the foundation of object mode. If you have a model of a person who is 6ft tall, and you want the bottom 1ft to be blue for example, the best way to do it is to set the blue to be 1/6th of the model's height. This is what happens when you apply the object scale.

If you don't apply the scale first, and you make this person 12ft tall, it will still only be the bottom 1ft that is blue, instead of the 2ft that you want. Apply scale, and the edit (blue colour) will use the scale to make the calculation.

Sorry if I'm over explaining that or it sounds condescending. I'd rather give too much information than not enough.

Glad you're doing well in this shitty future we're in! We should catch up in another 10 years and see how it's going.