LOST -the iconic TV series- Legacy, etc

The only worthwhile "arcs" in that show were on Evangeline Lilly and that Korean lady.

As to episodes, I agree the first 60 or so were good, but only because they built suspense.
The latter 60 were painfully bad as they exposed there would be no payoff resolution.

If we want to blame it on the network and give the writers a pass, that's fine.
I thought the actor who played John Locke was very good, convincing, and Terry O'Quinn was a great supporting TV/movie role actor going back decades to Star Trek: TNG, he played multiple characters in several stand-alone X-Files episodes, in Lost, he played a great "mentor-philosopher" role. He's an actor I'm glad finally got his time in the sun with something resembling that role of a lifetime that epitomizes and defines an actor/actress decades after their gone like Bryan Cranston (Walter White), Heath Ledger (Dark Knight's Joker), Lucy Lawless (Xena), David Duchovny and Gillian Anderson (X-Files' Mulder and Scully).