Majority of altcoins are centralized and have no new ideas, they just rehash the same old ideas over and over with a new name and new advertisements. This is why they don't have real potential and any "opportunity" is just short term profit making at a very high risk.
Each project offers lessons in risk management, ecosystem growth, and the dynamics of supply and demand.
That may have been true many years ago with the first generation of altcoins, but it no longer is true. Most of the altcoins we see today are just fake projects that no matter what supply they have there will be gamblers who buy into them (fake demand). There is no lessons to be learned here if you ask me.