I just saw that facebook account kit is being deprecated. There isn't much information about what's the reason behind its depreciation or what could be the next steps/alternatives.
Yes, As per official statement : from September 9, 2019: Account Kit will stop integrating with new apps. Existing integrations will continue to function normally.
Does anyone know why they deprecated it? Any technical insights/learnings?
"The product has yielded high maintenance costs, but relatively low adoption". Read full details here.
What are the alternatives now? or are they planing any successor of it?
They not announce any successor for it as far as i know, but there are many other alternatives available as open source which obviously have certain limitations. What I am using currently will mention here.