I've been thinking about this a lot lately, sometimes I get tired of all the frameworks and tools that are available. I just want to build things. That's is why I decided to make a side project with purely PHP and jquery (yes jquery :). I am familiar with vue.js and react but lately, I notice that I am making less progress with frameworks such as nuxt.js and next.js. At the end of the day, you just want to get things done.
And there are quite a few examples of successful projects that don't use frameworks. Like e.g. nomadlist by @levelsio. They develop new features so quickly that I start to doubt frameworks more and more.
Don't get me wrong I think for many project frameworks are useful, but if you want to get a lot done and you don't want to focus too much on the techniques, I have doubts about your statement.
During my career, I've developed custom frameworks (way more than I wished for - at least 4), and they all came out of specific necessities - stuff existing frameworks either lack, or catered to the lowest common denominator that wouldn't fit the desired approach. Most of them started on top of existing frameworks, extending over time, upto a point where they basically replaced most or all functionality from the base framework. They weren't perfect, they had bugs, of course - but often worked quite better than the code they replaced.
The one thing I learned while doing this is that it works well - you start from a familiar, robust system, and focus your effort on what you need to improve on your specific scope (eg. module initialization, event handling, database extensions, templating, etc) over time and as needed and to cater your needs, but using a holistic approach - design for big picture, implement for a specific case that can be extended. However, there are some pitfalls with this approach to take into account - integration with the base framework should be well thought of, and clearly defined in a way to reduce coupling and avoiding the situation where you have to maintain your own dogfood as well as the integration with someone else's dogfood. This often isn't easy, and requires a bit of planning, but it can be done.
I personally spend lots of time looking for pre-built solutions, its almost fanatical, after being burnt by my own home grow inventions (at the time)
And even worse, a known vulnerability on a popular framework could have hit you harder.