UWP desktop application doesnt display ShowAppointmentsInline=true, UWP mobile application works fine. simple implementation as below
<schedule:SfSchedule x:Name="Schedule" Grid.Row="1" ScheduleView="{Binding CurrentScheduleView}" ShowAppointmentsInline="True" HorizontalOptions="FillAndExpand"
Locale="{Binding SfScheduleLocale}" FirstDayOfWeek="2" VerticalOptions="FillAndExpand" DataSource="{Binding Schedules}">
<schedule:SfSchedule.MonthCellStyle>
<schedule:MonthViewCellStyle
BackgroundColor="White"
TextColor="Black"
NextMonthBackgroundColor="White"
NextMonthTextColor="Gray"
PreviousMonthBackgroundColor="Silver"
PreviousMonthTextColor="Black"
TodayBackgroundColor="Red"
TodayTextColor="White">
</schedule:MonthViewCellStyle>
</schedule:SfSchedule.MonthCellStyle>