Playtesting has certainly helped me get a new perspective on how other people build and design games, but in terms of what it means for my own project it is of limited use. I don't see a lot of ARPGs as compared to some other genres (e.g platformers, horror, cozy), and when offering my own critique I keep in mind the intention of the game as opposed to what I think it should be.
With playtester feedback, this has been stated already but it bears repeating - they are excellent at determining when there is a problem, but they are generally not good at determining what the fix should be. If your goal is to incorporate playtester feedback, then it's necessary to have a statistically valid sample to draw from. Where you hear the same complaints over and over is your clue as to where to go, but that doesn't mean that what they suggest is the right course of action.
I also keep in mind the intended audience for my game. ARPGs appeal to a certain crowd, and some complaints I've received are the result of the player not being my intended audience - a good example is in the difficulty. I certainly want my game to be enjoyable, but it is meant to be challenging much like the RPGs of old. Now if that challenge comes from unfair mechanics or bad controls, then that's very different than the challenge coming from the nature of the game itself. One is a problem to be solved, while the other is the product of player subjectivity.
When I do my own reviews, I will sometimes let the developer know if I am their intended audience or not. If it's a genre of game I don't care for, then I will often restrict my feedback to the more technical/mechanical parts of the game. I don't want the developers to think they should chase the opinions of people who won't ultimately play their game, but I do want them to hear feedback from another game developer who understands that side of the process.
Basically, be receptive to feedback and don't get defensive when you get it, but evaluate it holistically. We have our own preferences and biases, and nothing a player says should be taken as gospel. They are just data points, and it's up to you to determine how to interpret and act upon them.