Most investors and investments in recent times always come under self criticism given the fact that, most investors get to measure what prize Bitcoin is at the point of investment with the unit which they are willing to buy and consider it too small for a portfolio boost. Not minding that these are just building blocks to having a strong portfolio, more like the fittings to it.
Though it might be considered way too small, it has its role to building a strong portfolio and eliminates procrastination or having to prepare for that large some which never comes.
Those who think this way probably lack knowledge and know nothing about the DCA method because with the DCA method, the amount you are investing doesn't matter much even though the bigger the better, but even if you are investing $20 each month, that's still going to get give you good results in the long run only if you are planning to hold your coins for a long term and aren't willing to sell them soon. DCA doesn't work very well for short-term, and one should rather buy low and sell high instead.
From the time I came to know about Bitcoin, if I had at least $20 each month that I could put in Bitcoin, today, I could have thousands of dollars in my portfolio based on how Bitcoin grew over time and achieved the $100k milestone this bull run, and we are still expecting another wave of the bull run by the end of this year hopefully.