I don't see anything too obvious.
You have been loosing referring domains and acquired a ton of links and the link acquisition stopped or stalled all at around the same time.
Does Google Search Console give you any penalties or warnings?
Most of the links are coming from the US and .coms.
Is this well-aligned to your target market?
I don't see any obvious anchor text manipulation and the backlink profile distribution looks good.
The change in links acquisition velocity probably does set off some sort of flag though, that would be my best guess without digging into it further.