Smart apps or smart infra - where do you stand?

Should I add features to my app making it truly cloud native or should I use smart infrastructure that make me going faster with no need to code? Is service mesh hype reasonable or should I rather look into more application oriented platforms like serverless frameworks or DAPR? When I have Kafka SDK in my app does it make it less portable, because I have bound code with infrastructure decision? And why this debate started in 80s and is still going on today? Let’s talk about that and tell me what side you have chosen … if not actually both.