Regardless of what country I have been in the only problem I have experienced whilst paying with cash has been insufficient change in a till which has been quickly rectified.
Digital payments? At best, just as quick as paying with cash but that rarely occurs. I have lost count of the times when a customer in front of me has a problem with their phone, not enough credit in their bank and the worst is when they produce a fist full of 'money off' vouchers and a 26 baht digital refund is required.
Digital currency, a hackers dream, and they can spend your hard earned anonymously in the dark web, trying to recover money from the banks in the UK is relatively easy if your card has been cloned but here? Not the banks fault, you need to take the matter up with the atm manufacturer etc.
Best of luck with the money of the future but for me, if I cant see it, I can't count it, I ain't interested.