I 100% get your sentiment - I would be really frustrated if e-tickets were removed on the flow I commute on (I understand it's a different ticket type), so it's annoying to see the industry taking steps like this - even if it doesn't yet affect my journey.That is unacceptable. You should buy the more expensive mTicket then demand a refund from Scotrail for the balance. If you don't get anywhere, escalate it. If necessary, claim the difference from your bank.
However I would urge against anyone affected claiming the difference from their bank - contact Scotrail for sure, but as far as I know it wouldn't be valid grounds for a chargeback and could land people in trouble with their banks.