Urm - it's ALERTING GUI (on the Core) that makes use of Flash at present.
If you're talking about the client-side, I don't think we have anything that uses Flash.
Pretty sure they're looking at re-doing alerting anyway, but if in doubt you can always file a request here -- https://community.ivanti.com/community/enhancementrequests .
My apologies, Yes the Real Time Inventory and Monitoring that comes up through the Management console.
In which case the answer is "sort of".
So you need Flash if you want to access / configure it. That doesn't need to be on the Core itself, (can be on a/the device that runs a remote console).
If you don't care about alerting / the real-time stuff, you don't need it (until dev get around to re-doing it, among other things liberating us from Flash as it's scheduled for a much deserved death in 2020 anyway).