Investing in altcoins is not that kind of gambling because you need to do research first and also read different feed backs in different sites or places to make sure that the altcoin that you are investing is a good one and not that scam scheme altcoin. For me, Investing in altcoin will be gambling if you are a greedy person who just invest and then do nothing.
Yes, altcoin investments are too risky to have. Still, investing in altcoin is different thing from gambling which is the source to increase your earning when you are doing it with select altcoins like more established altcoins.
Yes, investing in altcoin is much better than gambling but it requires a lot of concentration and you have to keep in view to the markets up and down.
Indeed, the altcoin market is hard even for an experienced trader since the prices are unstable and it takes a lot of time trying to watch and understand how the prices change, so if you have the time and you got some experience in trading yeah you could grow a lot of bitcoin from altcoins, otherwise you are signing your own death wish because it is too risky.