Hi, No.
Thank you for contacting the Microsoft community.
As we understand from your post, you have passed Exam 70-533, and you would like to know if you can achieve the Microsoft Certified: DevOps Engineer Expert Certification by completing Exam AZ-400. We are happy to help.
Please bear in mind that, when an Exam is retired, it will qualify towards the requirements to achieve its corresponding Certification up to two years after the date in which said Exam was passed.
Since you mentioned that you passed Exam 70-533 more than two years ago, you must fulfill all the current requirements to achieve the Microsoft Certified: Azure DevOps Engineer Expert Certification.
The requirements to achieve the Microsoft Certified: DevOps Engineer Expert Certification are:
You can review the requirements to earn a Certification by visiting its respective Certification page and scrolling down to where it says, "Certification details" as shown in the image below.

Keep in mind that only one of the Certifications mentioned above is required, so you can choose the one that matches your profile the most. Once all requirements are met, the corresponding Certification will be available on your Learning dashboard within 48 hours.
We hope that you find this information to be of help. If so, please let us know by selecting "Yes" where it says, "Did this solve your problem?" located at the lower right corner of this post.
If we do not receive a response, the case will be closed and locked after one business day.
Best regards,