Why is it so hard to find the theory of everything? There are two main reasons.
One reason is that researchers must conform to the research topics that are fashionable, in order to remain accepted. Peer pressure is an extremely powerful force, and it is often underestimated. This is ideological pressure, of course.
The other reason is that researchers have been imbibed with ideas such as the following: "Whoever finds the theory of everything has read the mind of God." This sort of statements go back to Einstein himself, and they really are among the most stupid sentences one can make about God and about the theory of everything.
Mixing the TOE with God is stupid, because every theologian will tell you that you can read the mind of God by looking at your neighbour in the eye, or by praying, or when walking in a beautiful landscape. There is no need for a theory of everything to do that.
Mixing the TOE with God is also stupid because it puts the researchers under the impression that they are nearer to God than anybody else. Or that they must get nearer than anybody else. Or that if they succeed, they are chosen by God. Or alternatively, that if they fail, God did not want them to succeed. What a nightmare! This is the worst psychological environment one can create; with so much pressure, it becomes almost impossible for anybody to think about the problem normally, let alone to solve it.
Modern researchers have put themselves into a tough situation for finding the TOE. And the reason is always the same: there is too much ideology attached to the problem. If you look at the huge load of ideology, it is most probably that the TOE is found by somebody who does not believe in God at all.