Today Google has announced new steps merchants must take when unsuspending Google Merchant Center if Google Ads is also suspended. Previously you could get Google Merchant Center approved, even though Google Ads was disapproved. However, this is no longer possible per the latest policy updates.
Now, you are required first to fix your Google Ads suspension. Then you can approve your Google Merchant Center account (assuming you have resolved all issues).
Most merchants request a review without resolving any issues or doing the bare minimum. However, it is now even more important not to request a review if your Google Ads account is suspended. Because you only have a limited number of requests you can make. And every request you make extends the cooldown period, by 7 days > 14 days > 21 days, etc, until you are permanently suspended.