I'd argue the public don't know about the device. Apple and Samsung spend more on marketing and advertising that HTC are worth as a company - HTC simply cannot compete against that.
It's not like every person who purchased a smartphone knew of all the high-end flagships, researched them and weighed up the pro's and con's of each. The two devices they would have known of are iPhone and Galaxy. No surprise they were the two companies dumping most money into marketing/advertising and no surprise that they were the highest selling smartphones on their respective platforms.
The M8 outsold the M7, so I don't know how that's a 'failed design'. Seeing as you seem to think the success/failure of a phone purely on its design, it would make sense to release a design similar to a phone that sold more than their previous one.
HTC was always going to get smoked by Apple/Samsung/LG etc. They are larger corporations with more money to splash on advertising. When the iPhone and Galaxy is on every tv advert, every billboard, newspapers, website ads, trains, bus stops etc - it's kind of hard for the public to know about HTC.
Even if HTC did change their design to be that evleaks one (or some other one that's deemed beautiful), they'd still get 'smoked' by Apple and Samsung.
I don't get why you're putting so much weight into the looks of the device. It's much, much more than that.