Dropbox and Box are, for the moment, still startups.
Twitter isn't since they've IPOed.
Dropbox may have been a startup 5 years ago, but it seems like just a tech company to me nowadays. One that may stay independent, might sell to someone else later, who knows, but not really a "startup".
Twitter was never a small start up. It saw a pattern and invested millions in following and overtaking. The internet would be a better place without it.
I don't understand how the internet would be a better place without Twitter, please explain. I don't see them doing any harm. And if they are doing harm, could you please tell me what harm they are causing?
Take this with a grain of salt from someone whose handle is "Fasebook."
Twitter does lead to emphasising banal commentary, with less space for nuance. Your comment, simple as it is, is 50% too long for twitter.
The Post you're replying to would arguably be more impactful if it were short enough for a tweet- as it is, the point is restated two or three times. The first sentence is certainly enough to convey the message (and its subtext).
There are nuances in the other two sentences not conveyed in the first - "better without X" is not the same as "X is not doing harm". The way it's currently phrased is a better, more rounded request, giving the respondee a better anchor to work from.
You've actually highlighted how some nuance and context is lost by cutting things down to a 'soundbite'.