That was written in October. In the first few lines, in bold, it says it depends on how effective the vaccine is and how many people get it. I think things have moved on, given the surprisingly good vaccines on the horizon and what sounds like a plan to offer it to everyone over 18.
Air travel depends on what other countries do with vaccines and restrictions and if people can actually afford it when the economic impact of this really kicks in. I think business travel has probably fundamentally permanently changed now people have finally got their heads round video conferencing. I don’t really care to be honest, it’s environmentally damaging anyway, a bit less of it no bad thing.