Population req for Districts

[Lion King]

Hi,
Watching the game turning into the carpet of districts somewhere by midgame I decided to put a mod to tie placement of urban districts to city population (e.g. 1 urban district per 4 populations).
Turns out that disabling urban district placement is easy - that will only allow you to build in the existing slots:

<Districts>

        <!-- Only updating the line for DISTRICT_URBAN -->

        <Update>

            <Where DistrictType="DISTRICT_URBAN"/>

            <Set AutoPlace="false"/>

        </Update>

    </Districts

However, creating a modified and properly enabling it in the trait is a pain since there is no similar effect in the game, the effect simply won't work even if mod id is linked to the trait properly:

<GameEffects xmlns="GameEffects">
    <Modifier id="MOD_ENABLE_URBAN_AUTOPLACE_POP4" collection="COLLECTION_PLAYER_CITIES" effect="EFFECT_SINGLE_DISTRICT_ADJUST_AUTOPLACE" permanent="true">
        <SubjectRequirements>
            <Requirement type="REQUIREMENT_CITY_POPULATION">
                <Argument name="MinTotalPopulation">4</Argument>
            </Requirement>
        </SubjectRequirements>
        <Argument name="DistrictType">DISTRICT_URBAN</Argument>
        <Argument name="AutoPlace">true</Argument>
    </Modifier>
</GameEffects>

If anyone had an understanding/knowledge how to update this logic properly, would be greatly appreciated!