Hi did you find a fix to this? I test the checkout often and find it so annoying that it just knows who I am and just by my email prefills everything including my payment method. What if I want to use paypal? UGH the checkout as guest isn’t self explanatory and a tiny link at the bottom. It used to be that customer accounts were disabled by default, meaning that customer would use the guest checkout experience. but that option is no longer there. Shopify is trying to monopolize everything and customers that like some control get really annoyed and just leave checkout.
The guest checkout is not working for us. It is throwing a recaptcha error. Not sure if you found a solution to remove the default checkout page and enable guest checkout.
in case anyone is still struggling to figure this out, you can add ?skip_shop_pay=true to the checkout url. I can’t take credit for the solution, I found it here