I've worked at places with <50 people where the 2 IT people had "manager" titles, but they were just "the IT people" in practice - one handled user stuff, the other was focused on the client-facing infrastructure.

Our lone HR person was also the "HR manager", we had a single "accounting manager", and a couple more like that. Some departments ended up expanding and the "managers" did end up with direct reports, but that's kinda just how small businesses work, this posting sounds a lot like that.