

If a communication norm is just about other people’s preferences, why should they change? Who’s to say that other people’s preferences are more important than their own, particularly given that this particular preference is shared by millions of other people.
If inconsistent use of capitalization actually hinders understanding for some subset of their audience, then that’s a different story. My experience is that people are more likely to be annoyed than to actually have issues understanding all lowercase text. All caps text, on the other hand, is a different matter - and plenty of government and corporate entities are fine putting important text in all caps. But all caps text is a known accessibility issue. When I search for “all lowercase accessibility,” though, all I get is a bunch of results saying to not use all caps text for accessibility reasons.
If you have sources showing that all lowercase text is an accessibility concern, then you should share them. Heck, you should have led with that. But as it is, your argument ultimately boils down to “someone else should change what they do, that works for them, because it annoys me.”
From the feature comparison at https://github.com/meichthys/foss_note_apps only two FOSS apps support handwriting: Joplin (with a plugin) which gets a subjective 6/10 score, and TriliumNext, which gets a subjective 2/10 score.
I personally dislike Joplin but many people love it, so I recommend giving it a shot.EDIT: I installed Joplin using the APK from the site and both the handwriting and Excalidraw plugins were “not available on mobile,” so I have to rescind my recommendation. On my iOS device, the plugins didn’t even show up in the search.I think TriliumNext is great, but the mobile experience is still lacking (though they are tracking several issues to improve here). There’s no dedicated mobile app but they at least have a PWA. It also needs to be self-hosted, but doing so is straightforward if you’re already using Docker. The handwriting is done via a built-in Excalidraw integration.
Here are some options not captured in that list:
Obsidian is not open source, but also has an Excalidraw plugin. I’ve not used it yet but I’ve seen multiple discussions saying that it’s very well done and has additional functionality on top of base Excalidraw. There’s also an open source (MIT) plugin for Obsidian that adds support for handwritten notes. I only use Obsidian on my work computer and haven’t used it either, though I plan to install the Excalidraw plugin Monday.
StylusLabs Write is FOSS (AGPL 3.0), multiplatform, and has a free Android apk available. Note that the Google Play version has had updates suspended. I just learned about it and don’t know how it otherwise measures up. I’m planning to check it out, though.
You can use any note app that has Excalidraw support, so long as you don’t need your handwritten text to be OCRed. That means that the following are all options: