I know that with RV - steps are unavoidable.
I had TT with single step only (one was Airstream) and they seem to be the best stair-wise, but then TT do bring other handling issues.
I bought Lance TC with side entrance hoping for good stairs and that was disappointment.
My dogs would rather go 6 scissor steps on rear entrance, than scale 2 side steps on Lance.
Generally I think you guys need to exercise more as even knee surgery can be exercised.
I am 63 and just this week climbed a peak 1200' above my house- lead by neighbor only 1 year younger, but still in bandages on his broken hand .
My father is 93 and he walks to upper bedroom just fine.
You guys loose too much of your life sitting.