From what I've read each of the objections you've raised, the above, battery discharged, dropped phone etc are user, not system, error.
Fair enough, but with a card, I don't have to worry about making any of those errors, or my phone mysteriously refusing to work for no apparent reason, which has also happened.
Have you ever stood behind someone boarding a bus/tram/train who isn't prepared to use the correct payment method?
Not recently, although I did manage to inadvertently create a blockage and cause unnecessary delays to other passengers occasionally in York, when some readers randomly refused my card.
My problem isn't the use of phones per se, it's the unnecessary and forced addition of technology where there are simpler options.
For example, here the majority of people using public transport have some kind of season ticket which is valid on all local public transport; we don't need a debit card or a phone, although it is an option. This means getting on and off buses and trains is much simpler and faster, because no-one needs to tap in and out, and also because there are two doors on buses, so people getting on don't get mixed up with people getting off.
The system in York adds several unnecessary and complicated steps by making a new overly complicated, expensive system, which achieves less than a proven, cheaper system that makes using public transport considerably easier. It then compounded this by not accepting a valid card, so I had to pay more in cash, and block the queue.
And don't even ask about the insanity of the ticket barriers in Manchester Piccadilly...