Depends on the type of map. The announcements are good either way since they are a stern warning,alert, or compliment* to either teams. Muting it isn't the best idea. I havn't heard of a way to do so though.
koth, you should have it, yes. Depending on team size, alot of things go on. The timer isn't the most obivous thing in the world, the announcer helps with coordination and planning. (If that still happens anymore)
If this is your first time logging in after the migration (Feb 8, 2022), you must reset your password to log in. Follow this guide if you're having trouble