Just noticed that pkg-config for version 66.1 includes everything:

$ pkg-config icu-io --libs
-licuio -licui18n -licuuc -licudata

$ pkg-config icu-uc --libs
-licuuc -licudata

$ pkg-config icu-i18n --libs
-licui18n -licuuc -licudata

while recent icu2c version 76.1:

$ pkg-config icu-io --libs
-licuio

$ pkg-config icu-uc --libs
-licuuc

$ pkg-config icu-i18n --libs
-licui18n

This seems to be the issue: https://unicode-org.atlassian.net/browse/ICU-22610

Failed to compile imv due to missing icu4c dependencies, currently icu-io is included, but it seems that version 76.1 requires icu-uc as well.

Managed to compile it by changing:

unicode_lib = dependency('icu-io')

to

unicode_lib = [ dependency('icu-io'), dependency('icu-uc') ]

line 46 of meson build.