Limit on viewable devices? Alternative readonly view?

I plan on using traccar to track participiants on a sporting event.
Is there a practical limit on how many devices which can be viewable at the same time?
If so, is it a server or a client issue?

Are there clients ("htmlpages") which is more suitable for public readonly access?

Probably a thousand or a few thousands can be rendered without any issues at the same time.

Check this for a simple public readonly access:

https://github.com/traccar/traccar-web/tree/master/web/simple