Meg St Clair, like an overwhelming number of Apple cronies trolling this discussions forum since always, is a pompous æss who never understands (seemingly with purposeful intent) the concerns brought by users to the very forum where assistance should be found for their Apple devices. Instead, they find their most useful response to be things like, 'You should do what best meets your needs. No one here cares which phone you decide to use.' They basically accuse everyone in a very ableist and elitist fashion of being stupid and using their device incorrectly. Seriously, shut the **** up unless you have something that helps the user. This isn't the Eat-it-if-you-do-not-worship-Apple forum. What best meets their needs is an actual Apple-provided solution. In this case, the ability to leave voice control fully and always disabled.
It is not unreasonable to want for the home button to do nothing except for illuminate the screen, to unlock a device, and to navigate a device while unlocked. I posit it is very much a concern of accessibility and basic usability. Not everyone using an Apple device uses it the exact same way as you, Meg.
Personally, I cast a million votes for full home button option control that allows fully disabling voice control in the highest sense without affecting other home button, Siri, or accessibility settings.
iOS 10.x seems to have shortened the time required to hold the home button before voice control is activated. It's too quick that half of my attempts at screen capture (home + lock buttons) instead enable voice control, then immediately lock the device, no capture recorded. It's only like this because Apple changed it to be like this. Again, not everyone uses their device just like Meg uses hers. If you can imagine it, some people prefer Apple devices yet live with health concerns that limit their ability to press buttons together within a half-second sequence.
Alas, Apple was sure everything is just right. I tell you it is not, it can be better and inclusive of many more users with a couple of options alongside the existing options. I know that Apple likes revenue and more of it. Doesn't that happen by successfully reaching existing as well as new customers?
Copied to http://www.apple.com/feedback/ . Save your breath, Meg.