Does digital payments made cash wallets obsolete?
Nope.
Phones crash, apps screw up, Google arbitrarily decides your phone isn't "secure", batteries go dead, cell networks are sometimes unavailable (wallet app requires internet), merchant payment networks occasionally go down, etc.
I don't use digital wallets since the only options are Apple and their walled garden or Google who uses every transaction to profile you for targeted ads and deems your phone insecure should you do anything that might keep their eyes out of your life. But even using my "old school" debit card, I still feel much more secure always having some cash on hand for emergencies.



$150 is about normal these days. The pumps will usually have a little sticker somewhere that list the authorization hold amounts.
Fun fact: The auth holds used to be $1 way back in the day. But when prepaid debit cards came around, people could have a balance of $1 on them, get $50 worth of gas, and the station wouldn't be able to charge the actual amount (it would decline for NSF with no way to recover it as with a regular debit/credit card). That's why the hold amounts are between $75 and $150.
If you want to avoid the authorization hold, you can either pay cash or pre-pay with a cashier; the latter case will charge only what you pay.