Ding Liren is the current human “open” world champion, but there is also a women’s world championship, currently held by Ju Wenjun. Plus there is a world junior championship, world rapid championship, world blitz, etc. Magnus is probably still the world’s best human player, but he decided to drop out of the WC cycle because he got tired of winning it so often, basically.

The strongest chessplaying entities in the world are entirely machines, which have surpassed humans by enormous and uncrossable margins. The top engine for the past few years has been whatever the latest version of Stockfish is. The top human players spend enormous amounts of time studying machine analysis of various openings and game positions.