What is all this serverless talk?

On twitch this past week I build a crud application using the serverless architecture. Why? It's a big topic in the dev world and I wanted to see what it was about.
As a mobile dev your expected to know the full stack sometimes and I was wondering how hard it would be to switch from your standard api to a serverless one. So let me break down what I know so far...

What is the normal way?

Tech version: Typically you write an api using node and express and then run it from a server.
non-tech version: you have to write code that runs on another computer constantly.

What is serverless?

Going serverless means that you write individual code bits and pay when you run them

Why go serverless?

From what I've heard from my coworkers, serverless allows you to focus on business logic (not 100% what that means). It can also be cheaper in the long run for smaller applications.
Say you have a small app and 2-3 api calls. Why have a server running constantly when you can just trigger a section of code.

Do I need to learn a new language?

Not really but this also depends on what you know. If you have followed me long enough you know I think mobile dev need to learn js (node preferred) or python. Ultimately your coding options depend on the platform (AWS, Google, Azure) that you use. I use AWS or Google myself but I know Azure is pretty solid as well if that's what you're use to. I also recommend a language you could scale into a "normal" api if needed in the future.

So are you going serverless?

Basically. I don't build big applications for myself. I think going serverless is really cool for mvps (minimal viable product) and quick. No need to spin up a server when I can use AWS lambda or Google functions and keep it pushing. I think this could cut dev time almost in half as you have less steps to worry about. I also think this might be a game changer if you work in the big data/IoT space (don't quote me yet).

Thoughts?

Do you have thoughts on this topic? Think I could use a new perspective? Let me know.

P.S. I know I took off the comments. My apologies. I'm look at moving to a more secure platform for everything.