Technologist love to think through the technical implications of something, and assume these implications will be carried through legally.
The law doesn't work like that. Provided Dropbox adheres to both the letter and the spirit of the DMCA - or works with complainants to develop an arrangement both are hppy with the technical details DO NOT MATTER.
If it only was so simple... no matter what, it costs companies such as Dropbox a lot a lot of extra effort to appease all possible companies that can file complaints. That could cause them to go out of business, to have to charge more money, and/or be really restrictive to what files and users they allow.
A net loss for all users of the internet, especially law-abiding ones.
It does. The technical implementation can have a lot of effect on the chilling effect of a law.
Let's take the extremes. If the technical implementation is "we'll send a drone to fire a missile at your building", people will be much more scared to take any risk at all of hosting user-generated content than if the implementation is "you'll get a warning and a $5 fine".
Everything considered, "We'll arrest you and everyone that works for your company and nuke your DNS entry" is pretty chilling. If they only punished bank misconduct that hard...
Technologist love to think through the technical implications of something, and assume these implications will be carried through legally.
The law doesn't work like that. Provided Dropbox adheres to both the letter and the spirit of the DMCA - or works with complainants to develop an arrangement both are hppy with the technical details DO NOT MATTER.