Can GaN FETs be driven directly by logic level signals?
Driving the gate to 3.3 V is within specification, so nothing bad should happen.

However, note that Rdson is only guaranteed for 5 V gate drive.  The graph of Rdson as a function of gate voltage gives you some guidance what you will get at 3.3 V, but this is not a guarantee.  It looks like you should expect around 600 m&Omega;.  You can't base a volume design on "probably around".

Despite the marketing hype at the beginning of the datasheet about exceptionally low Rdson, the Rdson is actually quite high.  The gate leakage current is also quite high.

It seems the unusual aspect of this FET is that it can switch 100 V with only 5 V gate drive.  If you only need to switch 30 V, or can provide 10-12 V gate drive, there are much better FETs.  This is definitely a specialty part.  I haven't looked up the price, but I expect that says "specialty" too.

The package also pretty much requires hot air soldering for manual work, unlike a SOT-23 which can be soldered with a ordinary soldering iron.