Aljo's fight with Yan highlighted three fatal flaws with Yan's striking style...
1. Overreliance on kicking and checking
2. A tall stance
3. a tendency to shift into southpaw while punching
...all of which make you very vulnerable to takedowns. If Yan stood behind his jab and cross, widened his stance, avoided switching hitting, and used uppercuts to disincentivize takedowns, he would've done a much better job, but of course, this isn't exactly his style. Although his hand speed and technique is crisp, his striking style has very clear Muay Thai influence.
By the way, the speed at which Aljo can shoot for takedowns is nothing short of incredible. We're talking about a guy who went for a single leg off of Yan's leg kick at one point. Also, it's interesting to see how much you open yourself to takedowns if you go southpaw against an orthodox opponent, which is how Sterling got the takedown in round 2.