Why am I the only one who gets the constraints?

You know the code. Line by line, exception by exception. The others on your team do not, not the way you do. So you design around walls they cannot see, and when you explain why, their eyes go flat. This is not disrespect. It is distance — built by you, one solved-alone problem at a time. Ask yourself plainly: how much of what you know have you actually said out loud, before a deadline forced it out of you? If the honest answer is little, then the isolation you feel was not done to you. You arranged it, without meaning to. The code will not get simpler. Your team will not become experts by watching you move fast. There is one path forward: teach as you go, hand off pieces of judgment, stop treating your knowledge as something only you can hold. Share it, or carry it alone. Choose.