Because Safari's guts weakens the web as an app platform and strengthens their App Store, a favorable outcome for Apple. Adopting Chrome as the guts of Safari would defeat that benefit, and it'd be pretty hard to regain it. Safari's current "guts" - Webkit - can veto web hardware APIs and slow down broad support for PWA features, things that would help web apps compete with the App Store.
Post-Jobs Apple is the company that was willing to replace Google Maps with their own app to gain more independent control from Google, and they were much further behind when they did that. I can't imagine that company ceding influence & control over their largest platform threat by ditching Webkit. That's my 2c of speculation.
Post-Jobs Apple is the company that was willing to replace Google Maps with their own app to gain more independent control from Google, and they were much further behind when they did that. I can't imagine that company ceding influence & control over their largest platform threat by ditching Webkit. That's my 2c of speculation.