If you're running it continuously for a year, then you should probably be using a reserved instance and not lambda. Lambda is for short bursts, not 1 year of continuous use.
Not necessarily, especially in a large company setting. Lambda allows you to scale and take care of spikey traffic. It also doesn't require server management. Servers are a pain in the butt.
True, but ECS and K8s both abstract aware the hardware and offer cheaper 24/7 workloads and get past the cold start problem (at the expense of slower spike responses).