Use operator overloading for classes with non-ARC compiler

Project1.dpr

program Project1;

{$APPTYPE CONSOLE}

uses
  System.SysUtils, System.Classes, System.Types, Vcl.Dialogs;

type
  TStringListEx = class(TStringList)
  public
    // class operator In(const A: string; B: TStringListEx): Boolean;
    class function &&op_In(const A: string; B: TStringListEx): Boolean; static;
  end;

  TPointHelper = record helper for TPoint // Possible in class helper!
  public
    // class operator Equal(const A: TPoint; const B: string) : Boolean;
    class function &&op_Equality(const A: TPoint; const B: string): Boolean; static;
  end;

class function TStringListEx.&&op_In(const A: string; B: TStringListEx): Boolean;
begin
  Result := B.IndexOf(A) >= 0;
end;

class function TPointHelper.&&op_Equality(const A: TPoint; const B: string): Boolean;
begin
  Result := Format('%d,%d', [A.X, A.Y]) = B;
end;

var
  sl: TStringListEx;
  pt: TPoint;
  ret: Boolean;
begin
  sl := TStringListEx.Create;
  sl.Add('AAA');
  sl.Add('BBB');
  ret := 'AAA' in sl;
  Writeln(BoolToStr(ret, True)); // -> 'True'

  pt := Point(123, 456);
  ret := pt = '123,456';
  Writeln(BoolToStr(ret, True)); // -> 'True'

  Readln;
end.

Is it possible to overload for interface types?

No