...why did the aircraft have its landing lights on in mid-flight?

lights. The unusual thing was the direction the plane was going, and the rapid descent.
I would not call bullshit on anything as yet. I still wonder about that plane that went down off Long Island or somewhere like that.

That was a full feast of geese ingested into the engines.

This plane had reached cruising altitude, so probably not similar. Could be a loss of power of a different nature though.
But there are safety systems that are supposed to keep the plane functional in case of a total loss of electrical or hydraulic power; the RAT. (Ram-Air Turbine, basically a windmill that pops out of the side of the plane to generate hydraulic and essential electrical power in the event of a total power loss)

Whatever happened, the lack of a radio call suggests something dynamic, sudden, and very catastrophic.

Air France Flight 447 was essentially flown into the ocean due to incorrect response by the pilots to a mechanical issue that didn't actually threaten the craft. They never called for help either, but the aircraft sent several automated messages about its deplorable state as it augured into the ocean. If this aircraft did send such messages (Different manufacturer, but similar systems) they aren't talking about it.

I think there could be many reasons to cover up things, and I don't actually believe our government is all that truthful.
No, I don't spend time on conspiracy boards or whatever, I just do not necessarily believe the official story.

I was thinking a little too close to Long Island.

Yeah, there are still some unanswered questions on that one. Hell, it's mathematically possible it was hit by a meteor. Who knows. Sometimes complex machinery breaks. Sometimes due to cutting costs in maintenance. Sometimes due to stupidity. Etc.

There were way too many people direcly involved in the investigation (from six different countries too, IIRC) to keep any cover-up a secret, along with so many stakeholders who had no incentive whatsoever to participate -- Yeah, TWA just posted their first quarterly profit in ages and they're just going to go along with an cover story which makes them liable when the truth could have gotten them off the hook? And Boeing is just going to sit idly by just for laughs? If there was any discrepancy, Boeing engineers would have been the first to point it out...

The truth of it is TWA 800 is the last of the "Kooky Klinton/Reno Konspiracies" which refuses to die a dignified death...Because let's face it -- Clinton is the *only* person who would have had even a 1% chance of successfully covering it up...

Sadly, there HAVE been documented and damn-near-certain cover-ups of airliner losses, but no one ever wants to talk about those...