RadioOptionGroup is always re-rendering children

Index.razor

@page "/"
@using Microsoft.AspNetCore.Components.Forms;

<h1>Hello, world!</h1>

<EditForm Model=@Options>
 
 Radio buttons:

<InputRadioGroup @bind-Value="@RadioGroupVal">
    @foreach (var opt in Options) {
        <RadioOption @key="opt"/>
    }
</InputRadioGroup>

Click the checkbox:
<button type="button" @onclick="@StateHasChanged"/>
  
</EditForm>

@code {
    private List<string> Options = new List<string>() { "A", "B", "C" };
    private bool DoesNotMatter {get;set;}
    private string RadioGroupVal{get;set;}
}

RadioOption.razor

@using Microsoft.AspNetCore.Components.Forms;

<div style="border: 1px solid black">
    <InputRadio Value="Does not matter"/>

    @InitTime
</div>

@code {
    public DateTime InitTime = DateTime.Now;
    
}