This is Finley from the Social Care team at Shopify. Thanks for reaching out!
From what you shared, I understand that you see that your new development stores cannot disable the password page the same as your previous development stores.
This is indeed a limitation of development stores that was implemented recently.
Any development store created after August 17 2020 will need to be switched to a paid plan or be transferred to a merchant in order to disable the password page. This change will not affect any development stores created before this date.
You can see the message about this update in the notifications section of your Partner dashboard like so:
This means in order to access a website, the visitor must:
1) Enter the website by entering the password on the password page
2) Log in to the development store's admin
3) If the development store is used as a demo store for a theme or app listing, the visitor can enter the store without the password page appearing
Submitting a feature request
Our team is always looking for feedback. In order to organize and determine which features and changes are required, we submit feature requests.
I'd be happy to pass on the feedback that you'd like visitors to be able to access development stores without the password page. Every submission counts, so just let me know if you'd like me to do this!