When daySpeed= an integer and randomTickEffect= "ALWAYS", running /gamerule randomTickSpeed ingame during daytime returns expected value.
(ie daySpeed= 5, baseRandomTickSpeed= 3; randomTickSpeed= 15)
(ie daySpeed= 1, baseRandomTickSpeed= 9; randomTickSpeed= 9)

When daySpeed= a decimal number and randomTickEffect= "ALWAYS", running /gamerule randomTickSpeed ingame during daytime always returns 0.
(ie daySpeed= 0.5, baseRandomTickSpeed= 3; randomTickSpeed= 0)
(ie daySpeed= 0.5, baseRandomTickSpeed= 2; randomTickSpeed= 0)

If this is expected behaviour as a safeguard since randomTickSpeed must be an integer, making it clear in the configs might be helpful.

I ran these tests on Minecraft 1.20.1, Forge 47.3.12, with betterdays-1.20.1-3.1.1.1-FORGE installed only.