I guess this could work in the medium to long term because cryptocurrencies are a far better investment when they are done with long time periods. However, i believe this could still be optimized by not blindly investing a certain amount monthly. As we know, crypto is extremely volatile and a little optimization you can do is actually time your monthly investments at points where crypto is in a downward trend. Take some time to look at charts and all that, it shouldn't take up your time but being able to see the peaks and valleys will help you asses if the time is right to invest.