Any tips for someone new to it? Ive tried to get into it a few times and get too overwhelmed. I really like Cities in Motion (and trains in Factorio...), OpenTTD seems like a game I'd like if I could figure it out
What're you overwhelmed to? If it's signaling, try to use one way signal with loops at the end for turnaround. If you need junctions, look it online and just copy it without much thinking until you get better with this.
Turn off vehicles breakdowns, and there's setting to change towns to follow 2x2 or 3x3 grid, which will make building easier.
To make early money, look for two cities (they have City label on their name) with high enough population and close enough distance, and make 7 length station on both. You'll want to run 7 length on every passenger train in the end, it'll simplify the design.
The ui and menus may be confusing at first, but you'll get used to it.
I'd try watching the intro YouTube series by MasterHellish and concentrating on a particular industry to start with, it can get overwhelming when there's lots going on.
Play online, there's a small community running regular public coop games.
The downside is the games are typically pinned to an exact nightly build. I got tired of that, but it's managable for a finite duration to get you started.
Why do you like it? I haven't played much, but rather disliked OpenTTD because people appeared at a random station and didn't seem to care where you take them? If it is so, what is the point? If it is not so, what did I misunderstand?
I like Simutrans [0], in which people want to get from A to B and are willing to change between bus/train/plane. The routes which are central to one's network really need to be able to bear a lot of passengers.
There is an improvement in the options called cargo distribution (cargodest for short) which assigns them a destination among available ones on your network when they're spawned. This is a bit unlike simutrans where destinations are generated and then passengers only appear in your stations when it's reachable.
There were attempts to introduce more simutrans-esque behaviour in patches called cargodest, but it proved to be unacceptable performance wise for the map and network sizes that OpenTTD uses.
So, with cargodest does the cargo change from a bus to a train?
And without cargodest, what is the point of OpenTTD? I honestly struggle to understand this game if passengers appear randomly and pay the full price to go wherever you like to take them.
Cargo can change from bus/trams to trains anyway, either from manual orders or with cargodist.
It's probably also worth mentioning that cargo quantities are usually more limited at first. Primary cargo especially grows slowly. Passengers can grow very quickly if the player understands the city growth mechanics (the count is a function of city size), but even with cargodist if you make an actual network they will dictate their stop.
For me the appeal is more the mid-late game micro-optimisations, like how to make a junction work when there's constant incoming trains.