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I'm going to go out on a limb here and say that Fighting has benefited more from Dynamax than it has lost. In Lucario and Conkeldurr the type has access to some powerful priority moves to take down opposing Dynamaxes. Sirfetch'd and HDB Sawk also act as anti-meta mons in First Impression and...
With the (potential) rise of DMax setup sweepers, I think it's worth looking into ways to stop sweepers for types that have trouble with them without using their own DMax. A possibility is Heavy Duty Boots on a Sturdy mon which would act as a failsafe