Bitcoin is useless for investing in...from an investors perspective.
I wouldn't say bitcoin is useless for investing. With so many user around the world and large corporations showing interest, it is the safest crypto for investment. Altcoins offer explosive profits but successful alts are few and far between. You may get 10x gains from one alt while you write off investment for 10 others.
It's the safest, but investors who actually want to make money don't opt for the safest. Safe investments are for those who want to make a moderate income monthly/yearly without having to worry about their investment crashing etc.
That's why you do Research for any alt you invest in.