Raw icon names (that you cannot influence) often don't make a good replacement for proper alt text. Quite often they should not be read out at all. Furthermore, people forcing websites to use a font like OpenDyslexic will see these non-descriptive icon names instead of the real icons.

Just to complement other's responses, accessibility is a spectrum.

We ought to believe someone chooses to use an icon for aesthetics AND usability reasons. If the icon can't be rendered at all, it defeats it's purpose despite it having a "description".

Ultimately, if a well designed, user-friendly system doesn't work the way it's intended to, it is an accessibility issue of some degree. Albeit, some times more trivial than others.

The content "trending_up" is almost useless, a voiceover will not interpret the underscore as a space.

There are no ARIA attributes that link any of the text to the buttons.

It seems like the solution is to improve the accessibility tools. The information is all already there.

That's not the solution. The solution is adding the correct attributes to the markup. Attributes that are universally recognized and already work with a11y tools.

In this example we'd add an aria-labelledby to the button which references the span with the correct info.