Customer type is_subscribed field value is taken from the customer website: https://github.com/magento/magento2/blob/2.4-develop/app/code/Magento/CustomerGraphQl/Model/Resolver/IsSubscribed.php#L52

When you're updating the subscription via createCustomer/createCustomerV2/updateCustomer/updateCustomerV2 mutation the subscription store is taken from the current store: https://github.com/magento/magento2/blob/2.4-develop/app/code/Magento/CustomerGraphQl/Model/Customer/UpdateCustomerAccount.php#L115

Preconditions (*)

1. Magento version 2.4.2(probably more)
2. At least 2 websites
3. Customer Global accounts enabled

Steps to reproduce (*)

1. Create customer account in the 1st website
2. Subscribe to newsletter from the 2nd website
3. Confirm your subscription

Expected result (*)

1. Customer can see that he's subscribed

Actual result (*)

1. Customer can't see that he's subscribed as the subscription data is taken from the website he created his account in, but the subscription is created for the website/store he was browsing from when updating the subscription.

Please provide Severity assessment for the Issue as Reporter. This information will help during Confirmation and Issue triage processes.

• Severity: S0 - Affects critical data or functionality and leaves users without workaround.
• Severity: S1 - Affects critical data or functionality and forces users to employ a workaround.
• Severity: S2 - Affects non-critical data or functionality and forces users to employ a workaround.
• Severity: S3 - Affects non-critical data or functionality and does not force users to employ a workaround.
• Severity: S4 - Affects aesthetics, professional look and feel, “quality” or “usability”.