You say the security and battery issues "were solvable", so why didn't Macromedia or Adobe solve them? Adobe bought Macromedia in 2005, the era of Palms, Blackberries, Nokia/Symbian, Windows Phone, Microsoft Tablet PC; mobile devices were not a new surprise by 2005. Adobe did get Flash onto Palm mobile devices and TVs and early Android smartphones, and the experience was poor[1][2] - not just from those two issues; Flash sites weren't designed for mobile or touch or small screens. Customers had a choice of Flash-mobile devices, and preferred iPhones.

> "Ryan Lawler of TechCrunch wrote in 2012 "Jobs was right", adding Android users had poor experiences with watching Flash content and interactive Flash experiences were "often wonky or didn't perform well, even on high-powered phones".[9] Mike Isaac of Wired wrote in 2011 that "In [our] testing of multiple Flash-compatible devices, choppiness and browser crashes were common", and a former Adobe employee stated "Flash is a resource hog [...] It's a battery drain, and it's unreliable on mobile web browsers".[10] Kyle Wagner of Gizmodo wrote in 2011 that "Adobe was never really able to smooth over performance, battery, and security issues".[11]" - https://en.wikipedia.org/wiki/Thoughts_on_Flash

[1] https://www.palminfocenter.com/news/9692/palm-joins-adobe-fl...

[2] https://old.reddit.com/r/Palm/comments/ere0c/how_does_flash_...