I did that too. Quite often the project failed after those months because we'd built the wrong thing, or the landscape had changed, or the customer had failed to spec what they needed well enough. This was the "Waterfall" methodology, and Agile, with all its meetings, is specifically designed to fix that problem.
Besides, why can't we be lower case agile, and avoid all these meetings anyway? I write very detailed PRs with high level summaries, screenshots and videos, explanation of risks and trade offs, and deeper technical dives. Everything you need to know about what I'm working on is literally right there. I push up code early and often, it's not like I just want to sit in an isolated cave for 6 months and then emerge with a finished product.
My first job with daily standups was 2008 or so, and I just realized I left less than a year after they were implemented.
In short, I probably had less meetings in my first ten years in software than I did last quarter.
That said, the industry matured so much that experimentation that fold up as planned are generally doomed by large structural issue in the approach. 20 years ago, tweaking and digging your way in trench was the expected path since having to work around implementation details and bugs happened whatever you wanted to get done.
Agreed. when I started in the 90s I often got several months of focused work without many interruptions. Nowadays you have to attend meetings and always have somebody breathe down your neck. Hard to accomplish anything that requires experimentation over months until it works.