Dang it. I had forgotten that most debit cards now have partnerships like that.
However, remember that debit card transaction fees are typically quite a bit lower (no exact numbers to support my claim, but for instance my hairdresser only takes credit for larger payments; small ones she only accepts debit, or she would just lose too much to the credit card company).
So you wouldn't NOT support MasterCard/Visa, but they WOULD receive less money.
As for non-American credit cards, someone asked a similar question on Reddit and got technically valid but unsatisfying responses.
For instance:
https://www.reddit.com/r/amexcanada/comments/1j31ir0/comment/mfwmz5y/
Like, when they say "don't encourage the US" people don't typically mean jumping to Chinese companies instead. Not to mention UnionPay is definitely not as widely supported as Visa or MasterCard.
And while Japan isn't exactly notorious for its human rights violations these days, I kinda doubt JCB cards would be very widely supported. And could you even get one if you're not Japanese?
But like what even is a social media for women? I wasn't aware the ones we currently have were for men