Question about Use of Color and Contrast (Minimum) in charts

Hi everyone,

I have a couple questions regarding SC 1.4.1<https://www.w3.org/TR/WCAG21/#use-of-color> and how it might relate to charts and graphs. Specifically, the below supplementary note from Understanding SC 1.4.1<https://www.w3.org/WAI/WCAG21/Understanding/use-of-color.html> regarding color contrast has me wondering if I'm interpreting the criterion correctly:

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"If content is conveyed through the use of colors that differ not only in their hue, but that also have a significant difference in lightness, then this counts as an additional visual distinction, as long as the difference in relative luminance between the colors leads to a contrast ratio of 3:1 or greater.
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However, if content relies on the user's ability to accurately perceive or differentiate a particular color an additional visual indicator will be required regardless of the contrast ratio between those colors. For example, knowing whether an outline is green for valid or red for invalid."

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Would this mean, for example, that the below chart would still pass SC 1.4.1 by using color contrast as a visual distinction because the dark blue bar (#213C69) and the orange bar (#E67300) exceed the 3:1 ratio against each other (and against the background), and that because there's not a reliance on one particular color to impart meaning that this is acceptable? Or does reliance on color at all cause this chart to fail regardless of contrast ratios?

[Sample bar chart showcasing color contrast. The blue bar for 2024 has a 3.55:1 ratio against the orange bar for 2025, and both bars exceed 3:1 against the white background. There is also a third bar for 2026 that is patterned for visual distinction.]

Also, on a related note, if we were to remove the pattern from the gray bar, like in the below example, would the legend serve as a functional text alternative because it implies the ordering of the content?

[A second sample bar chart showcasing color contrast. In this chart there is not significant contrast or visual distinction between the bars, but there is a legend implying the reading order of the bars from left to right.]

Thank you very much for any guidance you might be able to provide! And apologies if this question has already come up and I missed it in my search, or if I've directed this incorrectly.

All the best,
Connor