I think a lot of people talk this way because they're scared, basically.
It's bluster. Noise to fill up time and push out any possibility of a more demanding discussion, of challenge to their self-image.
Some people are scared of revealing their own ignorance, so it's a form of insecurity, low self-esteem, stuck in an internal conflict with a belief that they deserve high esteem from others.
They could do a bit of work and educate themselves out of this ignorance but, for one reason or another, they can't (e.g. struggle with dyslexia), or don't. That can be because it's just too much hard work. Why bother when you can just bullshit? Or, because the status they believe they ought to have is genuinely unattainable - they see their 'should be' status and views as of equivalent value to those of a Professor or a Nobel Prize winner.
Also, people who have never tried very hard don't know where their real ability and intellectual status stand. They have no way of calibrating it, no idea how good they could be if they tried, or how much cleverer, quicker or harder-working they would have to be, to become a person of externally recognised high status.
If they did try, they might find out they can become a well-informed, interesting, useful, respected person. They might also gain more respect for the truly brilliant, hardworking and amazing, because they can see the gap between those people's level and their own. That's really healthy, knowing you're doing your best and that you are respected for the things you really do know and do, without having to pretend to be the same as somebody else.
It's not uncommon though, is it, for people with no real experience or knowledge of something to confuse their internal fantasy life with reality, with no idea of the gap in experience and attainment between the two. People who believe they know everything about being a real life football manager because they did well on a computer game, for example. So it is with 'research' ability.
Also, the world is big and complex, bad things are happening that we can't control. That's an external source of fear, that can add to internal insecurity and a lack of well-developed educational habits, to damaging effect.
*Note, all the above is my own speculation, based on observation and insight and intended to stimulate conversation. That's all. No claims of 'fact'.