Knowledge is what makes people invest in Bitcoin. That is why you see someone who thinks Bitcoin is too expensive to invest in, while they can just invest the little they can afford and do so consistently. You will also see people who are earning well but still find it difficult to invest.
Money doesn't really determine Bitcoin investment; though money is important, you can still have money and not invest. Knowledge is the principal thing in Bitcoin investment. That is why you can see a student who depends on their parents for upkeep money, but the person is consistently investing in Bitcoin. This is not because the money is too available, but this investment is possible because of the understanding one has about Bitcoin investment.
I rather say exposure and information can influence the mindset of people to invest in bitcoin although it also go down to the knowledge of a thing but in the general understanding, what everyone needs to invest in bitcoin is basic knowledge, I think is the mindset of people in regards to the value of bitcoin that makes them feel that bitcoin is expensive and for that it is an investment for the rich only, I have actually met some people that thinks exactly this way, individual mindset concerning how to invest in bitcoin can be reshaped by the privileged information they get from whoever or bitcoiners.
Anyone person that have a good income and still find it difficult to invest in bitcoin is either misifomed or not informed at all, I want to say this here, as long as I know that there are many people that have not invested in bitcoin, I will still want to tell us that some of these are as a result of how skeptical some them are about bitcoin, is not as if they have not heard about bitcoin and even how to invest in it gradually and hodl for a long-term but because they are not ready to face their fear squarely, hey understand this, no one understands bitcoin more than a bitcoin investors itself, practical is the real deal.