True, "cereal" is a catch-all term here for many things. I usually make oatmeal/porridge with a little bit of fruit. But using just 40g of oats.

Of course the Nestle-style cereals you're talking about are not ideal. But especially bad for you if you're eating 100g and not 40g.

Doesn't it rather depend on the particular cereal? I have wheat biscuits (a supermarket brand like Weetabix), 0 added sugar; almost any big brand cereal marketed at kids is extraordinarily sugary though.

Weetos are quite good (compared to other child-targeted cereals), honeynut cornflakes very bad, etc., IME you need to read the label though because it can be hard to tell.

Agreed, please don't eat cereal (at least the commercial ones) as they tend to be very high in sugar. It's like eating a tablespoon of sugar in the morning. Oatmeal and other non sugary breakfasts are fine.

NuTrail Keto Nut granola is pretty good if you want to eat cereal without a lot of sugar.

https://nutrail.com/