Depending on the method of payment on a credit card there is a different cost to Presto. A chip vs a tap vs a swipe vs online all have different costs to the retailer. And the amount of the payment also will change the fee. And apple pay is the most expensive of the lot (both the credit card company and apple both take a %). Costco and Walmart (Manitoba) even ban the use of Visa to save a bit of money (1% on the $1.1b of passenger revenue is $11M).
So not tech but $$$$. Will additional rides be generated just because we let people use Apple Pay? Not to offset the costs.
That is why they will open up the system but require cash payments for Apple Pay and any other credit card. I agree that Presto should have an app and allow NFC to be used from your phone but there is no need for Apple Pay which costs to much money.
My post, and the one to which I replied, were about loading your Presto card onto your phone to tap your phone.
However, regarding your discussion about Apple Pay for credit/debit, Apple Pay does not cost a single penny more to retailers. Merchants have not signed any agreements or set up any special technology to accept apple pay--this is a very common misconception; in fact, Apple Pay reads no differently to a payment terminal than a credit/debit card would. You can use Apple Pay absolutely anywhere that you would be able to tap the physical card that you've loaded onto it.
Where Apple Pay costs more is in that, since its percentage charged to retailers is the same due to not having any agreement set up with them for a separate percentage, they take some of the credit card company's percentage for themselves. This is why it was so late coming to Canada--our banks didn't want to give so much of their profits to Apple, but eventually they caved.
So, there's no discussion to be had for implementing Apple Pay credit/debit on the TTC because there's no such thing as implementing Apple Pay credit/debit. You can, in fact, use Apple Pay credit/debit right now 1) on the LFLRV SRVMs to purchase cash fares, 2) on the Presto self-serve reload machines, and 3) at collector booths for purchases over $10 (though those are frequently broken for accepting tap, period). Presto even currently tells people on twitter who ask about Apple Pay that they can use it on the kiosks.
And, similarly, once the TTC accepts tap debit/credit for fare payment on Presto readers on vehicles and in stations, there will be $0.00 total extra cost and absolutely zero added effort for processing Apple Pay payments--I don't think that "costs too much money".