I didn't know that about the usage of soldate and ecrivaine. I just looked it up. It is very interesting. It seems that feminine forms for job titles are widely used in Canada and are officially recommended in Belgium, but they seem to be discouraged in France, but are growing in popular usage there as well.
The Belgian "service de la langue francaise"
www2.cfwb.be/franca/femini/feminin.htm
says
"would feminine terms like magistrate risk shocking, upsetting, making laugh or indeed ridiculing?
It seems that the decree has helped to change the mentality. Little by little, slowly and surely , the use of feminine terms has become common, first in the media, the written press, radio and television, then in daily life, during election campaigns and finally in advertising."
I think this will be hugely important as it will change perceptions and operate subconsciously. I think the Academie Francaise is possibly resistant to its introduction in France. Le Petit Larousse accepted the feminine term écrivaine in 2008 in France.
But it is interesting that autrice as a feminine form for auteur was used as early as the 16th Century by some prominent literary figures. It looks like its use was perodically discouraged by men, such as Jules Renard in 1905, who wrote
"Women are looking for a feminine term for author. There is "bluestocking". It's pretty, and that says it all. Unless they would prefer plagiarist or ecrivaine."
I don't think there is any way of stopping the increasing use of femine terms, however the establishment seek to ridicule or discourage it. I think there will be a lot of opposition from the establishment in some countries, but times are changing and perceptions and usage have to change along with them. I think it is a good thing and will only help to accelerate positive change.