As someone with a partner who has ...

Mm, so you don't personally know what the experience is like. I have a partner with chronic pain, and though I can see what she does to handle it and get by, that doesn't mean I know what it's like. If I were to tell people with chronic pain, "Oh, it's manageable, I know someone with it and I see them get along fine, so you must not be trying hard enough," it would sound awfully insensitive, wouldn't it?

That might sound like a far-fetched comparison, but if you understood what experiencing executive dysfunction felt like, you'd know just how disabling it can be. Good on your partner, I'm glad they've found a solution/system/medication that works for them. But ADHD is a spectrum just as autism is. Even though I'm AuDHD, I know the things that help me aren't necessarily things that others would benefit from, because these conditions are highly individualized. To know one individual with one of these conditions and assume everyone else must be the same is beyond unhelpful, verging into offensive.