There is 'should' and there is 'does' :-) When IBM acquired Blekko they were moving people over to the web based version of Lotus notes at 1,000 employees a month (give or take) and with 450K employees that was a 30+ year timeline (it got faster as they worked out transition kinks but still) the point is that at certain scales these things are a lot more difficult for enterprises than you might expect.
The biggest challenge (as I saw it) was making sure that everyone could email everyone else all through the transition because if email stops, the company stops in that portion.
All of that to say that even though Airbus is one less than a third that many employees (133K vs 450k) its organization complexity is up there. And keeping complex organizations functional and efficient as possible during a large transition is often addressed by keeping the rate of change manageable (aka slower than you would expect).
People need to be trained, documents moved and converted, business processes adapted, ... In addition, solutions will have to be found for documents that exceed GSuite’s capabilities. 10 years? No, but 2-3 years for sure.
> “We expect it to take up to 18 months to reach every one of our 130,000 employees but our teams are already starting to work on a plan which will involve you and of course our social partners,” said Enders.
By the time announcements like this are made, there have already been lengthy successful IT pilots with much change management planning already conducted, partners engaged, etc. If they say 12-18mo, they may slip to 18-24mo, but definitely not multiple years.
That said, the other commenter is also accurate: a "full" roll-out will not mean 100% replacement. Things would break and it would be an irresponsible management decision to force some things that shouldn't be forced.
Source: I led a large MSO-->G Suite migration in a previous role.
