Re: SVG animations without SMIL

I disgree with your statement that there is no distinction between
"content" and "style" animations.

The whole point of CSS styling is that it gives the user the ability to
change the styling of a presentation. It is style not content for that
reason. To first order, CSS cannot change the content of either SVG or HTML.

It would be a misuse of CSS if it was allowed to add  'not' after every
verb in an HTML page.  CSS cannot change HTML text substantially because it
cannot change the content only the style.

Similarly it would be wrong to have CSS changing the timing of an animation
that demonstrated the speed at which somebody should massage a person's
heart when it stops.
Or changes the animation of a traffic stop light so that the light at the
bottom is red and the one at the top is green.

Just as CSS cannot or should not change the meaning of an HTML page so it
should not change the content of an SVG animation.

Just because the code that renders  the speeded up heart animation  or the
inverted traffic lights is similar to the original content animation is a
coding issue that has nothing to do with style or content.
Similarly, the browser can  choose to use SVG to display all the HTML
pages. That is an implementation issue which may be important in terms of
performance or code reuse.

HTML markup is how you define simple textual content. SVG animation mark up
is how you define content animations. CSS is how you tailor such
presentations to user's needs ensuring that the page content in both cases
is not changed.

We communicate our meaning to a machine via content and allow the user to
render/style that content in a way best suited to his/her environment
and/or
preferences and/or disabilities while trying to ensure that the meaning
cannot be changed by the user.