I personally prefer to invest in coins that have a chance of mass adoption...
besides Bitcoin you can invest in polygon matic, tron, polkadot, bnb or bch for the long term. you buy some now and hold for the next 5 years, surely you will see a high increase in the coins I mentioned but still DWYOR.
If you know what you are doing then that is fine my problem with this is that newbies try to do something like this and this is a problem as they do not really know what they are doing, also it seems they seem to think they can actually buy one coin and not check what is it happening with it for five years and we know this is not the case, for example we know that developers reissue the coins from time to time because they made an upgrade and if you do not exchange your coins during the time limit then you lose them, so you need to check what is happening with the coin at least once a week.