Mew's (evo) ability neutral shield

So I’m kind of new to the pokemon tcg so I really don’t understand most abilities so forgive me if I’m questioning common sense but for mew from evolutions his ability states that it prevents effects and damages from attacks of evolved pokemon so basically you can’t really do anything to him unless your pokemon is first stage or just doesn’t evolve

Yes, but since it’s an ability, it can be shut off by hex maniac, silent lab, garbotoxin, etc.