The natural consequences of Mozilla spending money on everything except on creating a the best browser in the world and working on marketshare (written in Firefox).
However, even if they did have the best browser how many installs would they get based on the quality of the browser? Most people don't care and those who care aren't significant slice of the pie.
Platforms dictate browser distribution because the average person is happy with what he god pre-installed or what google has shown as promo on their page.
They had >$6billion so I'm sure they could have put in some marketing and distribution partners.
Ladybird will show what one/very small team of devs can do developing a browser and what amount of $ could have been used for marketing and market share.