Altcoins for trading are much riskier than Bitcoin but also more profitable, so other potential altcoins can be used instead of choosing only Bitcoin for trading. Trading risk is something everyone has to accept if one wants to trade be it altcoins or bitcoins so I don't think trading should be limited to only bitcoins. But if one wants to make a long term investment then Bitcoin should be the first priority. However, trading is entirely a personal matter, so it should be up to the individual to decide which crypto to trade.
I believe that for trading you can use any asset in which you are well versed. If it's a highly volatile altcoin, then there's nothing wrong with that, but I don't like altcoins for long-term trades, for that you should only use Bitcoin. It makes sense to monitor several assets because they can pump at different times. But I also like trading Bitcoin.
Regardless of whether you like it or not, in fact, up to now, from what has happened, Bitcoin is more promising than Altcoin.
Every risk will indeed be proportional to the possible profit that will be obtained, but with Altcoin the risk is far above compared to Bitcoin while the possible profit is the same, so I think only Bitcoin is worth it, whether in the long term or short term.
Bitcoin prices are always able to recover and even increase drastically, so that is proof and there is no need to doubt it
Until now I have only traded Bitcoin, it is much safer in my opinion with a fairly large level of profit obtained.