It’s going to depend on the school and level

Given this example of eighth grade basketball, my kid technically had tryouts but everyone made the team. It was a small school though, and bigger schools may be different. He came in cold, not knowing the game but is a natural athlete. He had fun and learned the game and that one year was enough. I pushed him to play this year because he had been interested, he had a bunch of friends in the team, and he is an athlete. Importantly he’s not really tall enough for basketball, so eighth grade was likely his last chance to play. (It was funny to watch his crew of three soccer players and a hockey player take over the team and try to adjust their skills to a new sport)

Sports tends to get competitive in high school, especially for varsity teams, but there are usually options. For example my kid made the varsity soccer team after competitive tryouts. Part of the competitive nature was encouraging the kids to play competitive club soccer in the off season. To secure his starting spot, my kids spent the off season lifting weights, gaining about 30 lbs of muscle while cutting any remaining fat. Yes it was competitive. But he also joined a town league and a rec league for fun off season because he just loved playing: non-competitive, no tryouts