If a particular group is underrepresented there is a reason for that. It's not necessarily your fault, although unless you're very aware of ingrained sexist structures it's possible that you're contributing accidentally. It turns out that the reasons for the imbalance aren't good ones. It's not that women just love to do other things - there are pressures that actively dissuade them from pursuing technical careers. Most of this has happened long before they acquire technical qualifications and are applying for jobs. That IS sexism in our society, and it's not fair.
So where does that leave us white males working in tech?
1. We have to recognise that the gender imbalance is a problem and accept that it should be solved
2. We have to recognise there are ways we can help that are NOT simply "hire a weaker female applicant just to balance the genders"
3. Promote female participation! Sponsor school programs. Create female-only internships. Make sure that everybody in your workplace is actively educated about structural sexism so that things are as comfortable as possible for your female employees. Ensure salaries are equal.
We need to help send the signal to young women contemplating their careers that the tech industry welcomes them. Then, maybe 5 or 10 years from now, we'll be getting closer to equal applicants.
Funnily enough USB's inability to work over longer cable lengths works in its favour here. Generally we don't rely on anything working over 3 metres.
Wikipedia says "the maximum power supported is up to 60 W at 20 V, 36 W at 12 V and 10 W at 5 V" [1]. For a typical 3 metre 20 gauge USB cable 10 W power delivery will cause a voltage drop from 5 to 4.6 V. This is within the +0.25/-0.55 specified for USB 3 [2].
Since nobody can rely on the 5 V from USB to be exactly the charging voltage they need, there will probably be switchmode regulators in-line anyway. Device manufacturers will just have to spec these up a bit to accept higher input voltage if they want more than 10 W.
A common love/hate relationship I think; don't beat yourself up too much.
I think it's okay and even important to insist on open-source for a system like Plug even if you're not interested in using FOSS for all your computing. For many of the proprietary software examples you cited the "loss of freedom" is kind of nebulous (apart from the price tag!). The odds of a backdoor appearing in a product like Photoshop are relatively slim I think.
By comparison Plug is a perfect target - it is hosting documents and other data belonging to users who have likely made a conscious decision not to store it on the cloud. I don't think it's hypocritical to own a Mac and say that closed-source is not the right model for this application.
Why feel bad about it? It gets straight to the crux of the problem. If you're running closed-source software that is presumably taking updates from a third party outside your control, how much of an improvement is that over SkyDrive or Dropbox?
As far as I can tell the only problem with these services is snooping by intelligence agencies and the consequences of that (potential espionage, etc.). One could hypothetically argue that the NSA would be less willing or capable to snoop on data that is stored inside hard drives in citizens' houses - but from the outside we can never know that.
We need to have pretty damn good confidence that we have control over our own gear and data, and that means using open source software that is popular or interesting enough for third parties to review it.
So where does that leave us white males working in tech?
1. We have to recognise that the gender imbalance is a problem and accept that it should be solved
2. We have to recognise there are ways we can help that are NOT simply "hire a weaker female applicant just to balance the genders"
3. Promote female participation! Sponsor school programs. Create female-only internships. Make sure that everybody in your workplace is actively educated about structural sexism so that things are as comfortable as possible for your female employees. Ensure salaries are equal.
We need to help send the signal to young women contemplating their careers that the tech industry welcomes them. Then, maybe 5 or 10 years from now, we'll be getting closer to equal applicants.