it is important to write your ROS version in this issue.
I have checked one of my cAPs running probably something like 6.49.16 and in November updated to 7.16.2 - it has 560Kb of free space and seems pretty solid. With graphs and some logs saved to disk.
There are two problems in this issue:
1, We know Mikrotik made some changes to qifi-qcom-ac in 7.17, and 7.19. The update in 7.17 takes something around 300KB - so who had 500-600KB now has 200KB of space - which is not good when the device has less memory than any chinese aliexpress gadget for $0.50
2, something eats the free space. Probably not related to 1, since the same would happen, it would just take 3x the time - but 1 definitely makes it worse. It seems to me it started in 7.18.
You can’t see what is taking the space, everything is empty. Mikrotik support doesn’t help, they tell you to review your config or buy more powerful AX device - ignoring the fact, that with the same config, 7.16.2 devices run fine.
It seems 7.19.1 is slightly better in this, at least on my testing chateau, but it is probably too soon to make some conclusions, we’ll see.
btw - mikrotiks used to run for decades with 300KB 