If the colleague is provoking you, a dismissal answer could be a good call, like (hypothetical case) “you use iPhone and I use Android and I don’t make a fuss about it”.
But if the awkwardness question is something your colleagues asked, and/or they’re genuine curious why you do, a more objective answer could be “I compared the two and for the reasons x / y / z, I decided to use LibreOffice / Linux stuff instead”.
If the colleague is provoking you, a dismissal answer could be a good call, like (hypothetical case) “you use iPhone and I use Android and I don’t make a fuss about it”.
But if the awkwardness question is something your colleagues asked, and/or they’re genuine curious why you do, a more objective answer could be “I compared the two and for the reasons x / y / z, I decided to use LibreOffice / Linux stuff instead”.