I and 3 other developers left in the last 30 days (~100 people AI startup). My boss told me a couple of days after I gave my notice he'd give me $50k raise if I

I and 3 other developers left in the last 30 days (~100 people AI startup). My boss told me a couple of days after I gave my notice he'd give me $50k raise if I stayed for at least 6 more months (until they can hire/onboard more people). I still refused - I was unhappy there lately, and I'm getting $40k raise at my next job anyway.