Have you ever wondered why more jedi don't dual wield? Everytime they do they are more effective like when Obi-Wan fought Savage and Maul. It's not like they aren't allowed, I mean Ahsoka had two.
I personally like to think that the skill is practiced in basic form when all Padawans are starting out (and that if a situation calls for it, most Jedi would be able to adapt to using two just fine) but there are certain things to consider on why most would prefer not to dual wield:
Preference in fighting style
A honed coordination and balance when fighting
Adding an extra lightsaber for you to wield can just as easily complicate things as it may act as an advantage. Dual wielding is dependent on being able to split one’s concentration to both weapons and being skilled and balanced enough to not accidentally injure yourself while fighting.
I would say it is basically akin to rubbing your belly in circles while patting your head and being able to switch movements and still be in complete sync. It’s a skill that I imagine takes a long time to cultivate, but…unless this is a fighting style that is preferred, I feel most would not bother if they can do well with just one lightsaber anyway.
Remember that Anakin was dual wielding when Count Dooku bested him and cut off his hand, after all. It’s a cool skill, but it is something that really needs to be perfected first before one can consider it advantageous in comparison to wielding just one.
