Is this safe? Are you sure they are always identical? For example constrained layout draws twice and the Axes size and limits may have changed in the second draw.

Or asking the other way round: if the updates are redundant, why are we doing them in the first place?

get_tightbbox() which is called during constrained_layout is flagged here to ignore the cache - beyond that I can't find anywhere that we do an update on these values in the middle of a draw cycle (and the tests aren't complaining, though I know that's not fully exculpatory).

As to why we're doing them multiple times in the first place - in 3D we need to access these values in the tick drawing and the grid drawing paths, which might not both be called so both needed to potentially refresh the calcs.

In 2D, I don't see a reason - my hunch it was done without realizing the performance hit of recalculating that state each time.

# axis.draw()
self._clear_ticks_cache()

ticks_to_draw = self._update_ticks(_use_cache=True)
tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer, _use_cache=True)

for tick in ticks_to_draw:
    tick.draw(renderer)

self._update_label_position(renderer, _use_cache=True)
self.label.draw(renderer)

self._update_offset_text_position(tlb1, tlb2)
self.offsetText.set_text(self.major.formatter.get_offset())
self.offsetText.draw(renderer)

renderer.close_group(__name__)
self._clear_ticks_cache()

Actually, looking at this again, we can also cache within the get_tightbbox function. I see a similar speedup when profiling with fig.tight_layout() in the inner loop now, and the overall impact is more dramatic since we're doing everything twice.

Before:

After: