I only very casually like Star Trek and have never been confused when watching any series from the first episode.* I don’t know about all these fancy new Treks, but TOS, TNG, and DS9 were intentionally designed to be picked up during any random episode because that was how TV worked at the time. If you found a show during its fifth episode, you had no means of going back to the first four unless you happened to know someone who recorded them on VHS.

Lower Decks was also completely enjoyable to me even though my knowledge of the franchise is limited.

• I think it was Discovery we tried watching somewhat recently (not 100% sure on the title) where I was confused from the first episode, but it was in a “What the fuck are these creative choices?” and “Do people like this?” way.