Is UniFi Protect the Right Solution for Managing 90+ Retail Stores?

I'm currently the sole IT manager for over 65 retail locations and I'm testing out UniFi Protect on a Dream Machine Pro with a few cameras. The features I love include its clean interface and ease of use, especially for non-tech-savvy folks. I'm tasked with setting up camera systems for each store, expecting to add up to 4 cameras per site. My main goals are to find a simple yet powerful solution that allows for remote access, supports ONVIF or UniFi-compatible cameras, scales to manage 90+ locations, and provides user access control based on their roles. I'm thinking of deploying one protect device per store (UDM-Pro or Cloud Key Gen2+), but managing all these isolated systems feels risky. I'm looking for advice on whether this approach is sustainable and if there are better centralized solutions available.