Bitcoin payment is not the best fee-friendly method, specially with the crypto exchanges in Iran. I'd suggest you either allow more coins, or accept payments through Bitpay which enables customers to pay Bitcoin with other major coins in their wallet.
As Amir G said, the requirement to login when the Iranian users can't reach the Proton website is a major impediment. They need another vpn to set up Proton VPN.
Amax
Bitcoin payment is not the best fee-friendly method, specially with the crypto exchanges in Iran. I'd suggest you either allow more coins, or accept payments through Bitpay which enables customers to pay Bitcoin with other major coins in their wallet.
As Amir G said, the requirement to login when the Iranian users can't reach the Proton website is a major impediment. They need another vpn to set up Proton VPN.