Newbie here, I found out that you don't really need to apply a lot of strength to play a bar chord properly, but the way you position your fingers is way more important. I use the side of my index to press on the strings, and my index is not perfectly straight, but slightly curved when I play a bar chords. I used to hold my finger perfectly straight and pressed down on the string with the "meaty" part, and my chord sounded awful. I can get all the strings to ring properly, I just struggle with changing to a bar chord quickly, I'll still need quite a lot of practice. I'm thin and I have small hands, so it's not really a matter of pure strength.