@Anonymous ,A single Intune user can enroll up to 15 devices by using a single Intune license. We can see more details in the following link:
https://learn.microsoft.com/en-us/mem/intune/fundamentals/licenses-assign
Also, we can configure enrollment restrictions to set maximum number of devices that a user can enroll. Here is a link for the reference:
https://learn.microsoft.com/en-us/mem/intune/enrollment/enrollment-restrictions-set
For the devices we can manage in Intune, based on my research, I didn't find any official article mention this. So I think there's no limit now.
Hope it can help.
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.