You a very right, it is easier said than done since it is easy to write than to practice.
But as far as I know, it is better for a newbie to concentrate on Bitcoin other than altcoin since the rate of volatility between the two is with a wide gap.
As you said, altcoins have done more harm than good so ultimately we will need to stay away from such high-risk investments most especially as a newbie in the crypto market.2
Of course you are right, but in the market bitcoin is not the only asset that can generate profits. Volatility also exists with bitcoin due to supply and demand factors, actually I can say that ETH tends to have almost the same volatility as bitcoin so if your goal of investing in crypto is to make a profit then bitcoin is the one.
Volatility shouldn't be the best reason why you would choose bitcoin over altcoins as an investment asset. I tend to think of its use cases as a currency, its adoption as a means of payment, and the security of your funds with your keys as some of the advantages of why bitcoin is the best among other crypto assets.
I believe we are investing because we have seen their potentials to be profitable, and by having real utility cases that become more visible especially when hold for long term, then definitely those coins are the one we should focus on investing. While others have fallen on altcoins, I believe bitcoin has even more potentials to succeed and become profitable, not only because of its utility cases,