You’re right; I edited the post above. I misinterpreted the
The exchange rates for foreign currencies used are set by the issuer. They are based on the usual market sources and rates from card networks.
as based on Visa (“card network”), even though they likely mean themselves with “issuer” and put their random markup on top. 
For what it’s worth, you get the same exchange rates on other Swisscard cards (which are then 2% more expensive PLUS up to 2.5% foreign fees)
I have Wise, not Revolut so cannot compare them.
Currently the Wise fee for EUR to CHF is 0.423% and CHF to EUR is 0.23%. These percentages get deducted from the amount you are transferring, the reminder is then exchanged at interbank rate.
The app shows you the details of all this before you finalize the transfer.
Wise periodically changes the fees, but the EUR-CHF pair is quite stable. There is no change whatever the amounts transferred per month.
Edit: forgot to say this is for exchanging between wise accounts, when you transfer to another bank, you might have some additional fees, last time I paid 1.34 CHF to transfer CHF funds from Wise to UBS, seems to be a per transfer fee
Unless I am missing something, that means ultimately it is not really different from the Cumulus card. No additional FX fees but horrible FX rate, but you would still get Cumulus Points.
Revolut does the same if you have local currency balance or not, it will convert automatically your payment
UBS used to have all their cards (debit or credit) integrated into their budgeting/spending classification tool.
Which… when you have one provider for the account, another for the international card, and a third for the daily spending… just gets time consuming.