The coating is not the hazard. What it was hiding is the question
An inner pot is an aluminium bowl with a non-stick layer on it, usually PTFE. The scare story — that scratched non-stick releases something harmful — comes from dry-frying a pan on a hob, where the surface can pass 260 °C and PTFE begins to break down. A rice cooker never gets close: it stops around 100 to 105 °C at the base, and even a model with a cake setting is under 140. At those temperatures PTFE is one of the most stable plastics in a kitchen. So the coating itself is not the thing to worry about.
The aluminium underneath is. Aluminium is an amphoteric metal: it dissolves in acid and it dissolves in alkali. Tomato, vinegar, lemon, tamarind, sauerkraut — anything below about pH 4 — will take aluminium into the food, and the rate goes up sharply once the coating is gone because there is no barrier left. Plain rice and water sit close to neutral, which is exactly why the same pot can cook rice for a year without anyone noticing anything, and then produce a distinctly metallic tomato rice. The pot has not changed; the meal has.
That is also why the decision on this page is a decision and not a warning. A pot with scratches but no exposed metal is still doing its job; a pot with a silver patch is losing the argument, and the sensible response is a new inner pot rather than a new machine. Inner pots are standard parts: the model number is on a label on the bottom or inside the lid, and a replacement costs roughly a quarter to a third of a new cooker. The trap is not knowing that, and throwing away a machine that had another decade in it.
Three faults, three answers
Scratches and small flakes, with no bare metal, are wear. Switch to silicone or wood, stop using a metal spatula, never stack cutlery in the pot, and do not cook anything acidic from here on. The reason is not that it is about to fail but that the flaking has started, and flaking runs one way: the exposed edge sticks, the stuck spot scorches, the scorch gets scrubbed, and the scrub takes more coating. It ends at bare metal. Start looking up the model number now rather than on the day it matters.
A silver patch ends the cooking pot as a cooking pot. Stop using it for anything acidic, get the model number, order the part, and check three dimensions when it arrives — outer diameter, height and base diameter — because a pot that is two millimetres off either will not sit flat on the heating plate or will not let the lid close.
A button that needs several presses is usually the membrane behind the key rather than the electronics: the carbon pad wears through, or the contact oxidises. Unplug it, take the bottom off, and look at the membrane for a black worn spot or a hole. Cleaning the contacts with a pencil eraser or a little alcohol brings some of them back. If the membrane is torn, a replacement panel is cheap for a common model and worth trying before the machine goes out.