As someone who is still relatively new to this side of the hobby, my experience has been dictated by the players around as much as the game itself. The first few games I played in a tournament/store setting was with my Destruction faction (Ogors and Beastclaw) back in first edition. When I went up against stuff like Sylvaneth and Sayl or other strong stuff, the folks at the shop just let me know, "You're going to get smoked". And we played through scenarios of what I may or may not do in certain situations. And other games, they would throw stuff like Tomb Kings at me, or whatever "Cities of Sigmar" was called back then.
I had an understanding that some matchups would be rough. Communication was the key to a pleasant experience. It's just like Magic or any CCG. You can bring your kitted out tournament deck or put together some fun jank. Or, put two new-ish players together.
The main difference is the time investment... and to some degree the money invested. But the money investment really... is not that much different. That's a myth. Really, it's the time investment of painting vs deck building, and the games are about 3 to 8 times longer.