ICO is just one way of collecting funds from investors, its like IPO when it comes to the Stock Market. The only reason why ICO is now illegal is due to SEC now regulating this market but before it, ICO was good.
Its not the way of collecting funds that we should be boycotting, it should be the team that isn't doing the honest work. There are way to identify them and scam accusation will stop them from doing it over and over.
Openly campaigning for ICO boycott may not work because this is a decentralized market and every trader has his or her investment plan. Boycotting ICOs will only come as a resultant of the negative effects of the campaign on investors pockets but that doesn't mean that all investors are loosing. Some are still making money from ICOs and are hoping it continues. That's the beauty of the market anyway