Yes and no. You can overclock memory beyond what it is advertised, typically by increasing one or more of these; voltage, latency, and clock speed. This; however, may introduce instability to the system (as with any overclocking).
I'll say this.. and it may just be more confusing. You may find DDR4 3200 CAS 16 1.35V and DDR4 3600 CAS 18 1.35V. I would get whichever has the better price because of the higher timings on the 3600 take away from the higher clock speed (somewhat, not completely.) They could both probably do 3600 at C18. The drawback is that you have to tweak the settings yourself and hope it works if you expect overclock the RAM yourself. XMP profiles are awesome. Take advantage of them. If you find higher clock speed with the same CAS Latency and voltage, then you should have a better quality piece of silicon.
This is why we are not seeing any huge increases from DDR5 RAM performance (1-5%). You may find DDR5 6000 all day long, but it has a CAS Latency of 40ms. That's double the clock rate, but it's also over double the latency. There are good things about DDR5, but latency is not one of my favorite things about it. While you will get SOME performance increase out of faster clock rates along with higher latency, you will find the cost of the higher clock speeds to be higher than your performance increase.
Find your sweet sport for cost. If you find faster RAM that you like AND want to pay for, then go for it.