Mindset switch to not thinking of that communication as email. At least at my work place it took a while for people to not be overly formal and just go straight to the point, which slows things down. It's meant to be an instant communication channel after all
What stats are you working off of for those 3 decade estimates? Either way the point remains, the sentiment of "we should've done X decades ago" doesn't mean we should now be able to do it instantly, it just means we had the information and knowhow to start working towards it decades ago and we didn't do it.