Towing is a whole different situation. But if that maintenance schedule makes sense to you, it's your transmission.
I tow 27k lbs and change my Allison trans synthetic oil/internal filter at 50k miles. I don't mind spending a few $$ to keep my trans in top condition. My retired 06 Chevy DRW w/Allison trans had 325k miles on it hauling hot shot loads and I never had one trans issue. The maintenance $$ spent were a good investment.
As a side job, I used to buy late model cars with 100k to 150k miles on them for cheap with ruined transmissions from lack of oil changes. I could swap out a trans or even motor in a weekend. It was a lucrative side job.
Not changing oil in a trans/motor is the biggest cause of premature failure! Besides, changing oil is not that hard to do. For the trans, it involves removing 20 10mm bolts, prying the pan off and prying the internal filter off, push on new filter, install pan w/bolts and fill trans with new oil. It's an easy 1 hour job.