This is just the sensationalism of the media at work. When there is not much news to report (it is preseason), the press must create stories. This is one such example.
Honda invests more than $200 million/year in F1 and most importantly they are beating Toyota on track. They are now at the point where the engine is making the power and the reliability is way up. The chassis is no longer a Reynard champcar "pseudo F1" piece of shit and they have special Michelin tires. They are now in the best position they have been since their return in 2000. After 4 years of hard work, why would they quit?
Secondly, as long as Toyota is in, I think Honda has to be there.
I've often thought that the release of next gen. NSX would coincide with Honda's return to F1 prominence. The original car showcased their F1 technology and success. I hope the next one does it again.