No. It is not too late because there are many people who uses bitcoin who wanted also to invest but they have a question in their mind if it's too late. It's not yet too late because as long as bitcoin never stops, investment will never stop also. As long as there are users, there is bitcoin and if there's bitcoin, there will be an investment.
As of now you can still invest in bitcoin and I suggest you should invest now where the price is on the downtrend. Its never too late to buy bitcoin and anytime you can buy bitcoin. You can buy on the dip and then sell it when the price goes high. Just invest in bitcoin and do not waste your time on nothing.