I noticed a little more difference in crank length when I was "younger" (late 50s-early 60s) and only cycled for exercise. My various bikes have cranks from 170 and 172.5 through 175. For awhile I preferred 170 when my cadence was around 90 rpm. I found it more difficult to find a sweet spot with 175 cranks, and constantly fiddled with seat height and other adjustments to minimize knee twinges. (FWIW I'm 5'11" with 33" inseam, average leg length, longer torso.)
But by late 2020 my neck pain (old injuries and arthritis) had worsened to the point that I cut back on riding from around 6,000 miles a year to 500 miles a year. I started jogging and walking instead and doing more full body calisthenics including squats without weight or minimal weight (20 lb water jugs at home).
After awhile I noticed my knees, legs and lower back were no longer picky about crank length. Outdoors I usually ride a Diamondback Podium (2012 or so manufacture) that the previous owner had fitted with 175 Ultegra crankset to replace the FSA original. At first I thought I'd replace it, despite liking the older solid cranks like that year's Ultegra. But after awhile I adapted to the 175 cranks.
My 1989 Centurion Ironman still has the original 172.5 cranks, and I've tried it with 170 cranks (that 170 Dura Ace crankset is now intended for my early 1990s Trek 5900 OCLV). For the past couple of years the Ironman is mostly fulltime on my indoor trainer with the 172.5 cranks. I don't notice any difference between it and the Diamondback with 175 cranks.
The one time I did find myself getting picky about crank length was the year I tried Shimano Biopace ovoid chainrings on two different bikes, the Trek 5900 with 170 cranks, and Ironman with 172.5 cranks. The oddball Biopace rings felt better to me at a slower cadence, around 70 rpm, and with shorter cranks. For whatever reason those Biopace rings felt weird with longer cranks and at a faster cadence. But they felt good grinding up climbs at slower cadence.
I've added more weight workouts in the gym and that seems to reduce my sensitivity to crank length, saddle adjustments, etc. And my aerobic capacity has gone to hell after a bout with COVID in late 2021, so I quit trying to spin at 90 rpm and mostly grind along at 60-70 rpm now. My legs are pretty strong compared with my lungs, so the slower cadence suits me better now.
Same with the Matrix spin bikes in the gym. No idea what the crank lengths are. I haven't even bothered clipping in since my shoes are all fitted with SPD-SL or old school Look Delta, while the gym bike pedals have SPD on one side, flat on the other. I just wear Adidas Daily 2.0 sneakers (comparable to Five Tens) with relatively stiff-ish soles suitable for weight training, rather than my cushy running shoes. Takes a minute to dial in the saddle height and position -- and the saddle height post has fairly coarse adjustments in full centimeters, rather than the infinitely adjustable seatposts on "real" bikes. After that it doesn't feel much different from my own bikes, although the pedaling sensation on the spin bikes is uncommonly smooth compared with "real" bikes outdoors or on the trainer. But my output, heart rate, etc., are the same. No knee or hip problems.
Based on a sample group of ... me ... my conclusion is that reasonable full body strength training may reduce sensitivity to crank length and even saddle position.