Two sides of the coin.
Competition will spur operators to gip lower transaction fee to merchants, increasing take-up rate.
Users will be given sweeteners to use a particular ewallet (this is debatable, as ultimately somebody has to pay for these sweeteners).

Downside of too many players is users cannot utilize one wallet exclusively, resulting in opportunity cost of having cash stuck in multiple wallets. Not every merchant accept all wallets, although I observe TnG is slowly gaining dominance.

Maybe you need to rephrase this, for ktards have poor comprehension.
They will think we do have over 10 cc issuers - Maybank, Ambank, SC, Citi,...