We all know that air travel generates environmental pollution, and that it is very difficult for very large planes to avoid this pollution until ecological fuels appear to replace current kerosene, or another energy alternative. And we are more than 20 years away from that happening.
And since current flights have no choice but to pollute, airline companies deceive their customers by claiming that they buy carbon offsets (to plant trees in distant countries) and thus compensate for the pollution they generate.
Buying carbon offset credits has become fashionable among many companies, and they know perfectly well that it is a lie, but with this propaganda they intend to "reassure" the conscience of some of their passengers. It is what is now called “green washing” and that many companies do.

Today it is very clear that the propaganda of planting trees in developing countries is not sustained, and that its effect on the climate is not diminished. In the first place, in reality, much fewer trees are planted than they say, and what is more, those that are planted are felled in a few years and many end up burning.
But I recognize it is a good "speech" that serves to deceive the naive, or those who are hoping to be deceived to ease their conscience.
A few weeks ago, the assembly of the International Civil Aviation Organization ( ICAO ) declared its will to be carbon neutral by 2050 in the case of international flights, but they did not say specifically how they were going to achieve it.
I think it's another example of volunteerism far from reality. When time passes and those objectives are not met, the people who declared those objectives will no longer be in their current positions, and those who replace them will say what they see fit. We all know that over time things tend to be forgotten.
Therefore dear friends, we have “green washing” for a long time.