Does it make sense to use init-only setters on request models in an ASP.NET Core application to avoid mutation?

I've seen developers mutating request models in controller actions like this:

public class ProfileController
{
  private const string DefaultCulture = "en-US";

  public Task SaveProfile(string culture, ProfileModel profile)
  {
    profile.Culture = string.IsNullOrWhiteSpace(culture) ? DefaultCulture : culture;

    // then profile is passed to a service/repository to be saved to the DB
  }
}

Not sure why it was done that way, but I would like to avoid mutating request models. So, I'm thinking of using init-only setters on all request models to make them immutable and force developers to map to a domain model:

public class ProfileController
{
  private const string DefaultCulture = "en-US";

  public Task SaveProfile(string culture, ProfileModel profile)
  {
    var profileDomain = new ProfileDomain
    {
      Culture = string.IsNullOrWhiteSpace(culture) ? DefaultCulture : culture;
    };
    
    // This will cause a compile error when ProfileModel.Culture becomes init-only
    // profile.Culture = string.IsNullOrWhiteSpace(culture) ? DefaultCulture : culture;
  }
}

Are there any drawback or risks that I should consider if I change all request models to init-only setters?