The ()[]{} match manager is in parenmatch.py.  It imports Hyperparser, which uses pyparse.Parser.  When one types a closer, the corresponding opener is also highlighted and, depending on the configured style, everything in between.  Very handy for showing when enough closers have been typed. Edit => Show surrounding parens, ^0 on Windows, which is essentially ^) on US keyboards, highlights out to the nearest pair.  One can select one end of a pair by putting the cursor just inside a fence char.  (A tk Text cursor is between characters, not on.)

I don't think I would like automatic flashes when merely moving the cursor, or maybe I don't understand what you propose.

On the hand, moving to the nearest opener to the left or closer to the right could be useful.  ^] is already used for indent region, but ^{ and ^} (control-shift-bracket) are available and mnemonic.  What shortcuts do you know of?