Every decision is in your hands, I do not recommend buying bitcoin in large quantities when bitcoin is at a high price, there is no certainty that the bull market will make you a big profit from buying bitcoin. My suggestion is to exchange the altcoin you have for Bitcoin then save it until bullishness occurs again this year. If this is a good start to your decision, do it in principle in your own way.
I agree with you. In this case, the decision is in OP's hands because of course BTC has a fluctuating price so it definitely poses a risk and of course it requires strong courage to put OP's investment profits in Altcoins to btc because of course only those who dare to hold BTC for the long term can will get big profits. So of course everything is not without risks.
Indeed, buying BTC when the price is high is very risky because of course there will be a correction which of course could be a big correction or a small correction. The point is that in this case, buying BTC also requires calculations and waiting for the right moment. but for those who want to invest in BTC for example for 15 years or more, of course there is no problem because they will certainly have the potential to encounter very high BTC prices in the Future.
It seems that exchanging Altcoins for BTC is certainly a good idea and OP can make a good profit if the BTC price rises high. Yes, of course OP still has to be himself and continue to seek insight and information and of course the decision is in OP's hands.