GL’s are generally good in ALL game modes, and are great consistently, datacrons may make them more superior for a while but they do not need them.
Of meta counters require great modding, omicrons, datacrons, some require a lot of kit knowledge to work. Some benefit for a short period when very new due to lack of knowledge on kits, new abilities yet to be balanced and incentive datacrons to rush them.
This is a very balanced game in general, the fact Rey and SLKR are still very powerful demonstrates that whilst we see temporary power creeps they often rework to re-balance.
Off meta teams tend to settle into being powerful in one or two modes. Through locking power behind omicrons. And settle down into the meta once the powerful hype subsides.
I fully anticipate the protection disruption to be countered in future releases. I think GLAT will have an in built resistance and JML or GLLO if massively impacted will get uplifters or reworks to counter it.