This is someone who appears to have gone full crazy by at least 2014, ten years ago by now, also corresponding with when Russia illegally annexed Crimea, interestingly (IRA influence operations would have begun around 2013). This is one of the oldest posts that I find on FSTDT however (the oldest here seems to be from 2019). The relationship to Kremlin disinformation may not be direct, but many disinformation websites, like Global Research, ramped up their massive pro-Assad and pro-Putin opportunistic false flag "anti-globalist" alienation disinformation too. Then divisive campaigns amplified anything that was easily noticeable as a potential weakness. Victims of the traps end up wanting to destroy NATO, to support dictators and to be against Ukraine, to push paranoid alien invasion panic, moralist sermons, etc. A promoted disease of the mind and of society.
In any case, 911 conspiracy theories began soon after the attack which is older, but it has also been swallowed into agglomerative anti-Western disinformation conspiracy theories like QAnon.
Crackpots have their idols, and the founder of that conspiracy theory activism website, Richard Gage, was apparently an architect. Not a qualified forensics expert and not a physicist. Assuming that he were, a single crackpot's opinion never replaces a scientific consensus. In his case, he had no actual evidence to justify the grandiose conspiracy theory that all the actual experts who have worked on the investigation are only corrupt to the bone goons singing a common dictated story. It also denies the amount of fuel and time involved. It even ignores the separation of powers between elected officials and agencies.
It's true that Bush promoted false "intelligence" bypassing expert assessments (stovepipe), in this case the claim that Iraq had WMDs. It doesn't mean that 911 was a false flag operation.
Conspiracy theorists love claiming that facts are stories or narratives, to promote a false equivalence and mislead, pretend that their ridiculous stories could be valid, etc. The result is confusion and alienation.