They are easily removable. They are heavy, so be prepared for that. Hop on YouTube and search for your oven mfg. you will find videos that show you how to take the door off.

Some easier to remove than others. I think our GE wall oven you have to remove a couple screws, but it’s been a while so maybe not. Samsung removable. Our old 24” Frigidaire the door just slid off.

ETA the newer oven doors are quite a bit heavier than the old ones. probably due to better heat retention

The user manual may have instructions for door removal. The hinge springs can be very strong on heavy doors, and the removal procedure may involve flipping a latch on each side to hold the hinge in a specific position upon removal to facilitate reinstallation ... the hinge may close if the latch isn't set to hold it, resulting in a large challenge to get the door back on. There are different hinge designs/mechanisms ... important to follow the correct procedure for the particular door involved.

Another vote for the side opening oven doors on Bosch.