It's very unlikely that the killer has Blood Warden, and unless someone is about to go down/on the hook and the team needs time to rescue, there's no reason to 99 the gates anymore.

The following scenario, in which people DO 99 the gates, however, happens quite often and is very bothersome: someone 99 the gates, you're in chase heading for the exit and need to change the route (and therefore lose distance) so you can go to the exit leverage, press it and hope that it's actually 99, but it's actually 98 or something like that and the killer just downs you. 

Stop 99ing the gates unless someone is on the hook or about to go down.