Crèche or not to crèche?

My little one is nearly 2 and started going to creche when he was 17 months. He absolutely loves it there and enjoys walking in every morning. Our son goes 4 days a week. My brother in law has 4 children ranging from 13 years old to 2 years old and they've never sent any of their children to crèche. They planned it so that they would be at home with their children (they use TV and mother in law to help with minding their children. My husband and I have no help or let the children watch TV). We think creche has been amazing for our son as he gets interaction, is confident and loves going. We also have an 8 month old at home, so that gives me time to look after her. My brother in law is intent on putting things down and says that crèche is a way of getting children out of the home and that all children at crèche after a couple of years get bored and don't want to go anymore. They heard this from someone who runs a creche apparently. It's hard to hear, because they think they know it all when it comes to raising children, they've been there, done that. I'm confident with our family set up and how we are raising our children, but when someone keeps telling you how or what things we are doing is 'wrong' in their eyes it is so off putting and gives me a feeling of insecurity when I'm around them. We live very close to each other and see them most days. I don't see that point of view at all, it can't be true that toddlers get bored of crèche? Any advice out there or ways to deal with such negative views would be really welcome. I don't want our children growing up around their cousins and their parents with such negativity when it comes to a difference of opinion. At most points, their views come across as we don't know what we're doing, they've had 4 children and are the experts. Has anyone else experienced something similar, how do you stay calm and manage this?