Late 2019-2020 Mordekaiser top is basically season 3 Renekton
There really is not very much depth to his kit. There isn’t anything wrong with that either, but it means he has to be in check in terms of raw stats. This was not the case for season 3 Renekton - a kit that on the surface was very easy to grasp and lethally effective with very little practice. Therefore, it was very difficult to tell the difference between a good Renekton player and a bad one. That is basically Morde right now. There really is not depth to his kit. You spam spells off cool-down without worrying about a resource to manage. The deepest aspect his using his shield/healing, which probably gets used incredibly well by good Morde players. However, it does not really matter currently since Morde does not require much practice or skill to be effective with.
In fairness, Morde likely won’t carry a game either. That was also true with season 3 Renekton: unless ungodly fed, you’ll become more of a background champion by late game. Things are a bit different now though: late games don’t really occur. Damage is much higher, and Morde still has one of the best ults in the game when it comes to isolating a single target and removing them from a fight, and forcing them to build an item they likely don’t want to unless they are an ADC.
To be clear, I do not think Mordes kit is that awful. There is nothing wrong with simplicity, but I admit I’ve grown tired of resourceless champions becoming spam bots with little recourse. I think numbers adjustments would do him well, but as it stands he is one of the most frustrating top laners to face since he nullifies skill difference pretty substantially.