> The reason is that micro frameworks give you more flexibility and in large projects this is gold since you have to deal with so many requirements and multiple stakeholders

Not my experience at all. The "new requirements" you mention are always about business, not technical. Frameworks like Rails, Django and Laravel solve a pretty good bunch of the technical challenges which, in my experience, are common to the 90% of everything we build in most web based companies.

I've seen this argument of let's use flask/sinatra/express/fastapi because I need the flexibility/it is just a simple service too many times. And every single one ended up in a frankestein mix and match of 10s of other libraries that some developer ( now gone, of course) decided at the time was the best thing in the world until he got bored.

Also, you're not forced to use everything in these frameworks. If you think your application just needs routing, you can also use them and call it a day. If it happens 3 years down the line that you need an ORM, then you have it right there waiting for you.