For business, I use the Personal Kanban Task Organizer. It has an Outlook integration, so the tasks planned for today show up in my Outlook calendar.
I implemented it as a desktop software, it's available for Linux and Windows, it keeps your personal data on your local computer, no cloud communication, FLOSS.
Would a self-hosted static website be an alternative?
You could use your HTML skills, rent a cheap virtual server with nginx, and buy a web domain. Advantage: You are not dependent on the existence of a free platform provider, so your blog will still exist in 10 years.
Lazarus (https://www.lazarus-ide.org/) has built-in support for the configuration folder ($XDG_CONFIG_HOME) in the user context and in the global context:
financial.com provides web applications to visualize financial data for traders and investors. We develop and host tailor-made solutions for banks, exchanges and authorities.
Reminds me of broot (https://dystroy.org/broot/).