A live answering service is a reasonable first fix for after-hours maintenance calls, and most portfolios that use one are genuinely better off than a voicemail box. A person picks up, takes a message, and relays it to someone on your team. That's real coverage.
What it isn't is coordination. The answering service takes a message, it doesn't triage urgency against your actual policies, open a work order in your PM software, or dispatch a vendor. Someone on your team still has to read the message the next morning and do everything that happens after the phone call, which is most of the actual work.