As a brand new sim racer, where is it worth investing time and DLC for multiplayer racing in the current meta?

Bought ACC and Dirt Rally 2.0 and have been learning tracks and playing career mode in ACC. As a new player coming in 90% of cars and tracks seemed locked behind dlc. Im reading how some people think the meta is shifting to LMU and then of course theres iracing. Any tips on where to spend time money and effort coming into it at this stage?

What about places to build driver rating? Most ACC lobbies seem empty. I joined pitskill.io but that too feels relatively empty. Maybe im looking in the wrong places but the whole thing feels intimidating on where to begin.