Valid points within the science we know, but it is probably wise to consider aspects outside of settled scientific knowledge:
- So far, Ebola outbreaks were confined primarily to tropical regions of Sub-Saharan Africa; we will only just now be able to study how "well" the virus spreads "airborne", i.e. by commercial airlines, and we do not yet know what happens when the virus encounters a completely different set of hosts/environments/influences it wasn't exposed to so far.
- While Gorillas are often associated with Ebola outbreaks, bats are considered the most likely natural reservoir of the EBOV. You'll probably have a hard time finding gorillas in your neighborhood, but bats
In the 100 or so years we have been really studying viruses, we have seen a virus mutate and change its infection vector exactly ZERO times.
While this is probably true, the science we acquired during these 100 or so years is often based on epidemiological conditions and assumptions that no longer apply, or have changed dramatically, or which have been made considerably more complicated because of the way the world changed since the Spanish Flu -- not talking about those things we just kinda missed. Point being: aside from hemorrhagic fever making clickbait headlines right now, it's the same with influenza: we'd better not underestimate it, be it airborne, avian or whatnot.