The reason I hate Soylent is, as several other people mention in this thread, the over-blown claims made in their crowd-funding drive.
Before any work with nutritionists or dietitians the Soylent team were claiming:
> "You can finally join the easy, healthy, and affordable future of nutrition."
> "What if you never had to worry about food again?"
> "For anyone that struggles with allergies, heartburn, acid reflux or digestion, has trouble controlling weight or cholesterol, or simply doesn't have the means to eat well, soylent is for you."
> "Soylent frees you from the time and money spent shopping, cooking and cleaning, puts you in excellent health,"
> "By taking years to spoil"
> "there is much evidence that it is considerably healthier than a typical diet."
Some of these are just enthusiastic US marketing. I'm in the UK where we have stricter rules for advertising, so there's some cultural clash there.
But some of them are sleazy and not truthy.
That bad-feeling is retained by many people, even though the Soylent team are now working with real food scientists and being more careful with the claims.