I would imagine that some investors who have been in the market for less than 4 years can be considered new investors. It takes a long time to accumulate Bitcoin in particular. If you reach the excess savings level in the middle of 1 cycle, you can sell if you want. But you have not reached your savings target and you have made some money and you want to sell and take a profit, this is never a sign of an investor but a sign of a trader. It is not right to sell your holdings until the time limit or until you reach the excess savings.
Ten years is too big to call someone a new investor because for me I don't think that's how such should be addressed, a new investor is someone who just came into Bitcoin investment within months or highest one year but anything more than two is no longer new because you have learned all the things you Never knew before and that makes you now different from someone who doesn't understand Bitcoin investment yet, actually there are people who only spent four years in investing on Bitcoin but if you see their portfolio they are like people who has been investing for ten years and you cannot see them as new investor.