In my guitar playing days(55 years)I played acoustic guitar/mandolin. All the dynamics had to do with hand strength.

My 65 year old brother, who has played acoustic piano since he was 12, retired this year from many years of teaching. He bought a Yamaha acoustic piano for his retirement years.

The point is, using hand strength to effect dynamics on an acoustic instrument...be that of guitar or acoustic piano...those says are numbered. I still have visions of me playing bluegrass mandolin or guitar...ain't going to happen.

Dynamics can still happen on an electric instrument. My Les Paul playing buddy has known that since he was 17. He is now in his 60's and continues to make great music on a Marshall stack through a Les Paul.