It takes some serious imagination to view the relationship between the MLs as purely platonic. They express their love for one another is many different ways and are ready to die for one another. One ML is incredibly powerful and viewed as a villain because of something he has no control over, while the other ML is colder and more reserved and figures out the secret identity of the other ML. There is a lot of action and sacrifice, and the leads have a lot of fun banter with one another.
One of the actors have acted in both the titles, as a side role in The Untamed and as the lead role in The Male Fairy Fox of Liaozhai 3. Both titles have a focus on the soulmate relationship and love between two male martial artists. The Untamed has a lot of other plots going on too, but that is because it is a series and it has enough time to explore all the other plots. TMFFL's main plot is the relationship between the main leads. Both titles are good.