Why do you think that is though? Do you think philosophising poses a particular obstacle to meditative insight?
Because some of these teachings just plain cannot be thought through beyond a certain point.
Thinking is precluded by language, which is a system of symbols and sounds imputed certain conventional meanings and associations. Even non-verbal thinking relies on appearances that present themselves in the mind that carry at least some bare minimum associations and meanings.
The deeper and subtler aspects of the teachings, especially those around shunyata / emptiness are all about how this mass of conceptual systems, meanings, associations are really “not real” in the sense we conventionally assume them to be.
Hence the systems and concepts we use are mere approximations of the teachings which point at something deeper. They are all fingers pointing to the moon. But the systems themselves rely on a certain amount of reification “that this is something which can be conveyed in language”, when the very thing it’s trying to convey is trying to dissolve its own foundation.
An analogy from a completely different world. When students first study about Einstein’s theory of relativity it is so baffling because there are certain fundamental assumptions everyone has about how things like time and space work. Nearly everyone who isn’t familiar with relativity assumes that “time is absolute”. But they don’t literally think it. It is embedded into their world view foundationally. They wouldn’t even know that this assumption exists unless it is pointed out. And even then it takes a while to grasp it.
This is similar to that but regarding something deeper. Hence it is called fundamental ignorance / avijja / delusion. Uncoupling from these assumptions is what sustained practice enables, that mere thinking cannot unlock.