Ermmm, no, because that is like saying 2 + 2 = 3, because 3 is nearly 4

That Pascal code isn't anything fluent at all, it's just a series of method calls. The direct equivalent of the C# code would be (removing the use of WITH as an anti-pattern):

var myFluentThing := TFluentThing.Create
.DoThis(x)
.DoThat(y)
.DoAnother(z);

This is only possible, as is true for C#, if the DoThis and DoThat functions return an instance of the TFluentThing class.