Sorry - but yes. In this situation i think you are the AH.
I actually don’t think the door is the problem at all, I think it’s the colour.
The door itself is probably one of the NICEST features on what is otherwise a fairly ordinary period terrace.
This isn’t a grand Edwardian villa with ornate stonework where you’d expect an elaborate bespoke entrance. It’s a simple terrace and I actually think the proportions and detailing of the new door suit it well.
I did a few mock-ups because I was curious, and honestly just changing the colour completely transformed it.
Personally, I’d be looking at something like Farrow & Ball Hague Blue No. 30 or a traditional Oxford Blue. Both are classic heritage colours that work beautifully with red brick and make the same door feel much more Victorian/Edwardian rather than country cottage.
I also think the front garden is contributing to the impression. It’s a lovely garden, but it’s very soft, informal and cottage-style with lush planting spilling over the path.
That’s naturally going to make the entrance feel more “country cottage” than a formal Victorian townhouse, regardless of the door. A cooler heritage colour would actually balance that beautifully.
I also don’t think your partner has really done anything wrong. You’d already decided to replace the door, the fitters couldn’t source the style you originally wanted in such a narrow size, and needing an airlock for the cats is a completely reasonable reason to get on with it. That’s frustrating, but it’s not really anyone’s fault.
If it were me, I’d fit the door, paint it Hague Blue or Oxford Blue, and live with it before spending thousands replacing something that I honestly don’t think is the issue.
You need to focus on a cooler toned colour and I think your new door will be far nicer than the one on the left and will be actually the prettiest part of the terrace.
I prefer the glazing in your new door. It’s elegant, well proportioned and gives the entrance some character. The door on the left is certainly more traditional in style, but I don’t think it’s automatically a better looking door.
On a modest terrace like yours, I actually think the new door is the more attractive of the two. I genuinely think it’s the mustard paint that’s making it feel wrong, not the design itself. A cooler tone paint for the door will balance well against the warmth of the red brick.
So my final opinion not meaning to be blunt but yes - you ATAH.