In my opinion, Huawei should have released HarmonyOS globally since the release of their HarmonyOS 2.
Huawei phones since Mate 30 onwards is all pure HMS and doesn't come equipped with GMS, so it shouldn't make too much of a difference to those who still opted to buy Huawei phones despite knowing the limitation.
By doing so, it could have brough up the HarmonyOS market share and developers will be more willing to develop / port their app over to HMS after these few years.
If Huawei chose to wait for another few more years before doing so, by that time HarmonyOS is released globally, there is still be issue with very limited apps for HMS in the Singapore Market.