As a developer, you can't come in thinking you'll just get it. Bubble has renamed things for simplicity to non-technical folks and you need to take the time to learn their system.
Something I found great is Bubble's API Connector plugin and their REST Data API to. It lets you to call out to external APIs and CRUD into the bubble database. When my partner's app had a bit of "complex" backend logic that couldnt be easily done in the Bubble UI, I wrote a lambda function and they call it using the Bubble UI.
Bubble has been great for them. As their product / company grow that may not always be the case. But I think it'll hold up for longer than most developers believe, well beyond the initial prototype phase.
(With Zapier, I have used their so-called "Webhook" connector for that - set up an endpoint on my webapp that accepts a POST with a JSON payload, then make a zap that send data there in response to some trigger.)
But the biggest issue is that learning curve is even higher than tools like react. And the steps to do basic things are so tiresome it’s just easier to write code. UI prototyping is fast, sure. But not much faster than tailwind.
You want something pushed into a spreadsheet when you receive an email? That's Zapier.
Pushing something into a spreadsheet is certainly a widely used zapier idiom. In 2021, it is capable of far more complex tasks, though.
When I first looked at Zapier about 2.5 years ago, as a developer I found it limiting and just not useful compared to writing custom webhooks that I sometimes glued together with cron jobs, etc. But since late last year, Zapier has matured so much I am able to use it for almost every integration I need. It has probably saved me ~100 hours of development time in the past year alone.
I wonder if Bubble might have passed a similar threshold of utility, so that it is useful even to people who DO have good coding skills.