Yes, a lot of people doubted it, and still keep thinking that they are not going to make money. How many times does bitcoin need to prove to the world that it is a great way of making money? Did we not learn from our past mistakes enough? It should be noted that bitcoin WILL go up again, and by a lot, like more than double, and people who worry that they are going to miss, should get in right now and make some money when it gets there.
And people who think it won't, could stay out and not really invest at all, so they can watch us grow richer while they regret about it. I respect people who hold during come rain and snow, because those people face all the harsh bear periods, and eventually reach the sunny profitable periods.
If people think they won't be able to make money by holding Bitcoin, of course they don't understand investment well and they haven't learned about Bitcoin and I think it would be better for them to learn so that they don't just guess at things they don't yet understand. well and for some people who have a good understanding of investing in Bitcoin, of course they will take advantage of this opportunity to collect Bitcoin so that they can make a profit from holding Bitcoin, but if they don't want to learn about Bitcoin, of course it is difficult for them to believe that Bitcoin will be very good to use for future investment, of course this will be very profitable.