A single fortress in an empty space, yes.
But with some pre warning or a wall in front of it the story is pretty different.
If you have a lighthouse to see the attack coming you will get a Camel or two out in time, especially with production speed upgrades.
What cannot be is that, for example, a defensive building and 2-3 units can stop a considerable army of 20-25 units.
For casual players it is good that there are mods with higher HP or damage, but in rankeds defensive buildings should only serve to gain time if there is a certain equality.
The outposts thing can be checked but very carefully.
The issue is that defensive buildings can stop almost nothing.
Also the game has a lot more population now so armies can get a lot bigger too.
If a building can barely stop 2-3 units it becomes completely useless. Buildings have the massive downside of not being able to move, so they are always in a disadvantage against units.
Also there are siege units that simply outrange buildings. Why does a game need siege units if just 10 Infantry can basically born down everything.
Yes, this is extreme
But the actual state in the game is opposite extreme
???
Defensive buildings should be usefull, how was designated, not OP, not weak
The “paper buildings” with no attack degrade ranked MP as well, not just casual games