Its an issue for conscription. Army getting smaller every year. Add shorten national service duration. Then compete against industry for staffing. Finally only train males, ignore females.

Its also a problem that does not have a short term fix. Even if birth rate goes up today, it will only be seen/felt 18 years later.

Low risk for sinkie as no "clear & present danger" threats but Taiwan is facing the large dragon on the opposite shore. Taiwan like living dangerously but no time for bedroom fun.