\b and Indic word boundaries?

Hello. Yesterday I reported https://bugs.python.org/issue32198 but
then was pointed to already existing
https://bugs.python.org/issue1693050 and friends.

From reading these I came to find \b under
https://unicode.org/reports/tr18/#Compatibility_Properties.

I confess I don't entirely grok all the intricacies. So my question:
isn't \b the Unicode-recommended way of identifying full Unicode-aware
word boundaries in regexes? If not, what is?

-- 
Shriramana Sharma ஶ்ரீரமணஶர்மா श्रीरमणशर्मा 𑀰𑁆𑀭𑀻𑀭𑀫𑀡𑀰𑀭𑁆𑀫𑀸