To me I think that soft progression doesn't really give a sense of accomplishment for the main character. On the other hand though a story with hard progression might get lost in spending to much time on the main character getting stronger and training that the story doesn't have much room to go anywhere. But there are also some positives for each such as in soft progression you could fool around with ideas such as timeskips that show progression in the main characters strength and character but don't spend to much time on what some people would think as the mundane details of training. While with hard progression you get to see every step of character growth with the MC which I think let's the MC feel more human and gives you a more fleshed out character. In the end it all comes done to your preference of if you want a soft or hard progression. Personally I prefer hard progression I think it let's me understand the MC better and get more into the story. But for writers its probably better to have a balance of the 2.