libmariadb3 symbols changed in stable release (10.3), breaks ABI compatiblity

In Debian we use a libmariadb3.symbols file to track if and what symbols change in each release. The history for 10.3 has had now several symbol changes in last 6 months:

Examples:
https://salsa.debian.org/mariadb-team/mariadb-10.3/commit/f5804f0ac87b2301499ba8dd262d33fdbcfb44d7
https://salsa.debian.org/mariadb-team/mariadb-10.3/commit/122fbbb85f1b401f6d292d399fd6197055d81898

Full history: https://salsa.debian.org/mariadb-team/mariadb-10.3/commits/buster/debian/libmariadb3.symbols

Question 1) What is the policy on this?

Is this intentional or a bug? Were there decisions to ship new libmariadb3 versions in a stable release so that it is not fully backwards compatible or did it just happen? WIll you continue to do this?

Question 2) How to mitigate issues?

Should we just hope that the symbols changed are not consumed by anybody? So far I've seen only one complaint: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=951210

Should libmariadb3 be split out from the server package so that it would in the future be released independently with it's own version numbers (3.0.x, 3.1.x etc)?