I'm sorry but I think you are a bit too sensitive.
If I look at Marc's post, I see nothing offensive or degrading. He also suggested the software you could use instead, as you requested and he was just being honest.
So I see nothing that is anything but a respectful and honest post. Why do you feel attacked, might I ask?
If you just want people saying your work is great, then you should not post here. If an honest, and in my opinion true remark is posted, that is not what you had hoped for, then you can't react in the way you did as far as I am concerned. As you say, in the real world it's not about members or moderators and everyone should be treated with respect. So I suggest you do the same and respect the opinions of people that think your work is not the best out there. And there's plenty of material on this forum to prove that to be a fact.
So ease up on the "feeling attacked" attitude, because you are not. Look around a bit at the work of the mentioned modellers and then maybe try the sofware marc, and others, have suggested. You'll see that soon, if you go at it, you will see what is obvious to others but which you at this point, don't want to accept.
You can't call 2 days of modeling hard work. Ask those other guys how long their models took.. You'll learn soon enough what it really takes to make detailed, advanced models.
Good luck with that and keep on going, because it reall IS appreciated, even though some people don't think it is as good as you think it is.
And as you seem to want to know why.. well.. a few things I notice
- your model lacks a whole lot of detail
- maybe it's the screenshot angle, but some parts are not even symmetrical
- Dimensions do not seem to match the vessel you are replicating
- Some vital parts of the vessel are not there
But having said that, for sketchup, it ain't that bad.
Fred