I notice that a lot of the Inko-bashing comes from a fundamental lack of understanding Japanese customs and society.
Because Inko Midoriya is a quintessential Japanese mom.
Someone else had already addressed her status as a housewife. I'll update this post with a link once I find it again.
Inko's Guilt
Let's cut to the chase: Inko blames herself for her son's Quirklessness.
In Japan, pregnancy is a time of extreme discipline for women. Are you eating too much? Did you quit your job? Did you wrap your belly like you're supposed to? Any miscarriages, premature births, or disabilities are tied to a woman's conduct.
The sad thing is, Inko would not be alone in holding herself responsible. Her doctors, her neighbors, maybe even her husband would question what she did to Izuku.
Horikoshi outright says that her guilt is what caused her to gain weight.
It's important to note that in real life, there's a growing backlash over this very perception.
"Monster Parent"
Inko calls herself one when she takes All Might and U.A. to task for her son's injuries and constant run-ins with villains, but honestly she couldn't be further from the truth. Her demands aren't unreasonable.
This is another controversy in real life Japan. Parents who intervene on their child's behalf run the risk of being labeled "monster parents." It makes addressing academic ableism and bullying, etc. that much harder. (Not to mention that schools have been caught covering up ijime incidents.)
Inko was probably not entirely unaware of the bullying her son was experiencing, but she's under heavy societal pressure to let the teens figure it out for themselves. All she could do was offer a supportive home environment.
She's also been conditioned by Hero Society that the violence in U.A. is normal, in order to train the next generation of heroes. That doesn't mean she approves, it means she's pressured to keep quiet.
Look at her reactions during the Sports Festival! Inko was extremely upset watching it.
There is, however, a limit to what someone can ignore.
Inko showed incredible character development when she confronted All Might, going against social norms in order to protect and advocate for her son.
The way Inko is written is a fascinating commentary on Parenthood in Japan. But often it flies right over the heads for non-Japanese readers.