Day trading isn't as simple as just buying low and selling high, it just doesn't work much with altcoins in my experience you got to do it in BTC/USDT. If you take a look at the SNTR today, its almost worthless coin where you can't even see updates that can make the coin spike a bit to attract traders but with BTC the price can just swing in everyday where your chances of earning is much larger.
Day trading can be beneficial with bitcoin as it shows some significant difference in price during 24 hours. Altcoins are a little less volatile than bitcoin and it is actually not possible to make money via them in day trading. Long term holding is also more beneficial when holder is having bitcoin as it gains the most value. Even ethereum which is known as the king of altcoins cannot produce big profits.
It can be beneficial for others but it is still risky for most.
Altcoins was way more better than bitcoin to do trading. Having bitcoin to do trading has a higher risk of cutting your investment in an instant if happen that you missed the opportunity to sell/buy at the right time because its price is more volatile than altcoins.