I am happy to report that I have very successfully used about 10 mobile InterRail passes with no 'mobile' issues whatsoever (any issues would also have occurred with a paper pass). I always ensure that I have mobile phone roaming in the relevant countries (either by my phone contract, or by use of e-SIMs). Anyway widespread mobile data availability is absolutely essential for me for journey planning, checking on connection times and train delays etc. On one occasion I bought and used a mobile pass at very short notice - something not possible with paper pass.
Many years ago a friend managed to lose his main interrail pass mid-trip, but travelled around for a week just showing the journey record.....
Many years ago a friend managed to lose his main interrail pass mid-trip, but travelled around for a week just showing the journey record.....