I'm not going to defend Musk at all as he had absolutely nothing to do with the development of the Raptor engine.

That said, a rocket engine is nowhere near as simple as "cone that shoots fire with unnecessary wires". Most of what you see there are not wires, but high-pressure pipes. These can carry chilled propellants as part of the regenerative cooling system (where they run the near liquid-nitrogen-temperature propellants through the nozzle to cool it and prevent it from melting), or tap-offs to get a small bit of the propellant that's been heated up into a gas in order to pump it back into the fuel tanks as part of the autogenous pressurization system. Many of the lines there are for various diagnostic sensors that were used during early development, which were removed as those parts were finalized and the monitoring equipment became unnecessary. However, outside of sensor taps, it's nowhere near as simple as "just yank out those cables and pipes"... though I wish it were at times. As an aerospace engineering undergrad, things like turbopump design are murder with how insanely complex it can get, and just how narrow the margins you have.

Nonetheless, the Raptor v3 (the one to the right in the picture) is REMARKABLE in how much they've been able to simplify the engine. It's speculated that it uses a lot of advanced 3D metal printing in order to create internal channels and structures that would otherwise take the form of external lines. I can't speak much more on it than that, as any more detailed information is not available to the public - both due to it being proprietary information, and because rocket engine design is HIGHLY regulated under ITAR and most of it is required to be classified with a secret or top-secret clearance to get all of the details. But, if you look at any of the many, MANY other rocket engines throughout history, the Raptor v3 has to be one of the cleanest, slimmest engines outside of pressure-fed hypergolic engines (which literally only have two valves that you open; the pressurization of the fuel tanks provides the propellant flow).

Give credit where credit is due to the actual engineers at SpaceX who spent hundreds of thousands of man-hours developing this engine - ignore the Apartheid nepo-baby CEO who stumbles in after shooting up a dose of ketamine and tries to take credit for work that he had nothing to do with. Elon isn't an engineer, and barely has an understanding of physics. Anyone who has listened to him ask a question that wasn't pre-scripted with a prepared answer can immediately tell that he doesn't know jack shit, but instead just regurgitates what other people tell him.