Ah, is that why... I noticed this too but assumed it was due to some communist ideal of gender equality leading to more women tradespeople, wishful thinking I guess
If not for the war or other legitimate reasons I'd assume a preponderance of one demographic doing a specific job as likely a bad thing. I'm surprised it'd be wishful thinking.
You saw it in the US during the two world wars. Women got more rights and there was some interesting propaganda encouraging women to work.
https://en.wikipedia.org/wiki/Rosie_the_Riveter