It’s fine to eat 250g of carbs, though that seems high if you’re trying to be as far from obese as possible without being unhealthy.
It’s not fine to eat 250g of sugar. You’ll likely get diabetes.
Also not all carbs are made the same. Eating bread is not the same as eating sweet potato, as suprising as that may seem. Few carbs are good for you and you should make a concious decision about which ones to eat. Not to mention everything that usually gets added to carb-heavy food as those tend to be highly industrialized. Due to their convenience factor they’ve effectively replaced home-cooked carbs.
But perhaps most importantly, carbs have been showed to be linked to Alzheimer’s Disease though this isn’t yet mainstream knowledge:
https://www.ncbi.nlm.nih.gov/m/pubmed/15082091/
The cynical in me thinks “big food” must be trying really hard to hide this fact from society.