When it comes to getting stuck lids off of jars, I have gotten tons of mileage out of the idea that the vacuum seal is actually what's keeping the lid of e.g. a pickle jar stuck, rather than just tightness. If you take the tip of a butter knife, or the sharp end of a bottle opener, and slip it under the lip of the lid and pry carefully until you hear the "pop" of breaking the air seal, the jar should be way easier to open.
Not as many households have simple bottle openers like this, but I think it’s probably worth it just for this one use case.
If that doesn’t work, and it’s not a grip problem (which can be solved by using a silicone hot pad or rubber glove or wet rag), try inverting the jar in a small bowl and using hot water to change the game a bit re: pressure.
Update: a friend of mine in her 80s has a more sophisticated version of a silicone gripper to help open tough jars (that she’s pre-loosened by breaking the vacuum seal with the pointy end of a bottle opener)
