Growing a robotics YouTube channel

Hello,
I'm a French robotics developer, in my day job I code on a medical exoskeleton.
I recently started a side project where I'm building some kind of companion/pet robot that walks and can follow me in the street.

In the meantime I'm documenting the progress and explaining some stuff on my youtube channel.
You can find the videos here: https://www.youtube.com/playlist?list=PLZvbNAMaWQBl1rb4N9nYZDSVbkcV5tihL

I chose to target French audiences, because I felt that the space is empty, there are really few people talking about robotics in the French youtube. Whereas in the English one there are huge channels with millions subscribers.
So I felt that it was a better strategy to talk to the French niche.

I've launched the channel via a Linkedin post that reached 7k views, which made the channel grow to around 120 subcribers with the first video.

Since then I post on twitter, linkedin, sometimes facebook, to announce the new videos.
I post one video per week, and in 3 months I've grown to 250 subscribers.
I've targeted specific robotics/IA etc groups on facebook on linkedin which helped me gain more subscribers.

I'm thinking now about a way to keep growing, and also how to monetize this.
Do you have any suggestions to help me grow the channel? My content is very technical for now, maybe I should explain less and just show my progress so that more people can relate and understand.

Do you think that was a good idea to target French audience where there were no big channel (so lack of competition, but maybe lack of interest) instead of making videos in English where interested French people could still follow ?

Thanks for any feedback :)