Among the reason why whitelisting is important in cryptocurrency is the fact that it helps developers to place restriction on those allowed for events like presale, withdrawal and others in order to avoid spammers and unauthorized access to such events.
I don't like whitelisting because it goes against the idea of decentralization, whitelisting gives opportunity for restriction which is also control and that's something that's associated with centralization and this why people are advising against patronizing altcoins because how can a project that claims to be decentralized and will operate in a decentralized nature start off with restricting people from accessing their crowdfunding. They're meant to allow everyone to participate since they're decentralized but for project that aren't hiding their centralization then they don't have an issue with me but i don't see any benefits with whitelisting because if I wanted to invest in any altcoin, I can always get them when they get listed on an exchange and trade then for profits. Investing in Presale isn't the best advice either because most of the projects mightn't get listed on exchanges or give profits as you're anticipating.
Recently I begin to wonder why anyone will like shitcoins when we know well that every other coins/ token is linked to Bitcoin price movement since every other coins is transacted as a pair to bitcoins.
The thing be say many people no know wetin shitcoin be, dey see all as legit cryptocurency. Na we wey dey the system know wetin dey sup. E get people wey be say if you check their wallet, na just shitcoin full am and dem dey lose some and make some but for their mind they're cryptocurency investors (which isn't a lie) but they're doing more of gambling then investing. Many people dem never know the difference between legitimately project and pure pump and dumps shitcoins. Another reason why dem dey like shitcoin na because e dey give quick profits and you know say we Nigerian like quick money (which is why shitcoin investing is becoming very popular for this our side).