The flux system is not really that much unfamiliar to the shield/health regeneration in many FPS games nowadays.
Yes, I don't play FPS games at all. I found out about this game via my main Steam Group, eXplorminate, which is a 4X/Grand Strategy group. It's of interest to us 'cos it has some similarities to space based 4X games like Polaris Sector, Stellaris, GalCiv and Distant Worlds (the game map is quite like Distant Worlds map) and a lot of us are total space game junkies from a strategy point of view. But these games don't have any such combat systems.
My other two main genres are (mainly TB) tactical squad combat games such as Battle Brothers and XCOM and classic D20 style cRPGs from BG thru' Pathfinder: Kingmaker. Again, there are no similar systems in these games although I have remarked that XCOM on legend difficulty has some similarities with respect to the cat and mouse fighting model in that managing pod activation genenrally makes discretion the better part of valour if you don't like your soldiers biting the dust.
So I guess reaction to these systems is probably going to be somewhat dependent on the direction you came to the game from.