Had you continued your thought process you would've come to a completely different conclusion. Consider this:
you are stacked with shield cells and so am I. We meet in battle both with energy diverted to weapons and engine as we see fit, nothing to systems as we are stacked with shield cells
my fully energised lasers eat through your shields as do yours mine, we use our shield cells and again, the battle continues longer than would have been the case without shield cells, we enjoy it a lot more
problem is that I relied too heavily on sheild cells, whilst you tried to save them more conscious of evading me etc etc
now im out of cells but your not. Your better skill and use of the cells has given you advantage in the end game
im having to play harder and better to try to even things out. Maybe my flying skill will save me, maybe I have a better weapon load out or maybe I manage to turn and run before getting to SC
however it ends, shield cells were just another of the tools available to the skilled commander, just like a weapon, the choice of which shield generator to use or whether to go for fixed, gimbal or turrets etc etc
to say at this stage of the games life that shield cells have been fully investigated, their full tactical use in battle identified and understood (instead of just cell spamming against NPC sidewinders

) their weaknesses discovered etc etc is just not true and is unrealistic to suggest as such
Just another opinion