Part of SVG's accessibility importance is the ability to label and describe with
<desc>. The problem with
<title> is that it doubles as an accessible name and a hover tooltip.
This is the problem that made early Internet Explorer and
alt an accessibility disaster; authors started writing alternate text specifically for the tooltips, or avoided it altogether to prevent confusing sighted mouse-users, so I'm sad it happened again.
Later SVG specifications stated that
<title> should only be used for hover text if it had
role="tooltip", but this was never implemented.
It's not perfect, but it would be an improvement if we could disable the tooltip behavior with CSS/SVG presentation attributes, to avoid breaking existing content that relies on the old behavior:
<title pointer-events="none">A yellow shining sun.</title>