First, it aint you buddy…And, like my step dad always said: "don’t get old"!
Yes, that cylinder is gas filled, and is an "assist". So, there are a few possibilities. The tilt/steering tube might be tight, but that isn’t likely, try loosening the big locknut a bit. The assist shock itself might be damaged/rusted internally and binding. The good news here is that most dealers have piles of these things laying around from engines where the dealer added power trim/tilt..
The top pivot bushings like to bind up, usually from salt water though. The same is true for the bottom cylinder bushings. I’m guessing your engine is a fresh water unit, so this is less likely.
So, unfortunately, my nickel is on a damaged tilt assist cylinder….It might have simply "lost its charge" also…