It is absolutely insulting. The manager/administrator doesn't apologise, but instead is "sorry for how you and the Japanese community feel". They are dismissive of the concerns as just a "quick call" is proposed, in a short response to a detailed message.

Had I been thrown in this situation:

"Dear Marsf,

I'm sorry that sumobot was introduced to the Japanese SUMO community without consultation. I have disabled it, and the development team are working to undo the changes it has made. We will revert articles to how they were on 21 October. Contributions made since then by the Japanese community could be retained in the staging system, where they can be approved or rejected. Please let me know whether you would like this, or would prefer them to be discarded returning the whole system to the 21 October.

We very much appreciate the Japanese SUMO community's contributions and your work as locale leader, and we hope it can continue. Sumobot will remain disabled on the Japanese translation. If, with some changes, it could be useful to you, we can discuss that here, or schedule a meeting if you prefer.

Thank you"

In this exact situation, before sending I'd check it with my Japanese colleague.