Is my SIL lazy?

Well, I'm posting here on behalf of my parents because they are old and don’t know how to use technology. We live together with my brother and his wife in my parents' house. Since the first day his wife married into our home, she hasn't helped with chores around the house, like cooking or doing household tasks, as my brother mentioned that her parents pampered her and didn't train her in these things. She only does her and my brother's laundry and cleans their room; otherwise, she does nothing. My mom asked her to learn how to cook, but she refused, saying she has no interest.

Fast forward, they have kids, and she quit her job to be a stay-at-home mom (SAHM) because she disagreed with how my mom cared for her kids. She believes my mom is old-fashioned, refuses to listen to my mom's wise advice, and wants to care for the kids in her way. Initially, my brother and she wanted my mom to care for their kids so she could work, but due to conflicts, she stayed home to take care of the kids, leaving my brother with the financial burden. As a SAHM, she still doesn't cook or clean the house, mainly focusing on caring for her kids.

Still, she has many complaints, such as my parents crossing her boundaries and disrespecting her rules for her children. She claims my parents give her kids snacks every day, while she says no. She doesn’t allow her kids to go out with us without her presence. Frankly, we wouldn't want to hang out with her much because she's a control freak, telling us not to feed her kids certain things and constantly reminding us to keep an eye on them, as if we don't know how to handle it. It feels like she's keeping the kids away from us.

She doesn't work, so my brother has a financial burden, as he needs to pay for many things, including supporting my parents. My parents deserve this because they help take care of him, his wife, and their kids in our own house. He pressures her to get a job and lets my parents care for the kids. She claims to be looking for work, but it's uncertain if she genuinely is. I wonder about her capabilities. What do you all think about her?

Understanding why my parents hesitate to ask my brother to move out, it seems her actions pose challenges. She appears capable only of managing her own life and kids. The sustainability of their situation is questionable.

Updated: Since many of you asked, I think I should put additional info here. My brother’s financially not enough, how can he afford to move out if he works alone and his wife doesn’t work. We are staying with our parents but giving them money every month so our parents can sustain the house. My parents don’t let my brother move out first because they worry his wife might give him more burdens by not working, not doing house chores or cooking.