Assuming that all the en-suite won’t have a bath in them, I’d say a family bathroom with a bath is useful - it means anyone in the household can go for a bath without having to go through each other’s bedrooms.
It would be an occasional thing, but very occasionally a day visitor might need to use the shower etc, and a famiky bathroom might be better than going through bedrooms to the en-suite. Think a friend coming round after group cycle ride or other physical activity.
Agree that lots of people with small kids don’t want them to have access to en-suites. If you can lock them, that’s fine to cut off access, but most would then take the small children to a bathroom with a bath and it’s often easier if that’s a family bathroom rather than the en-suite which has a bath, as the bath might not in the child’s bedrooms, but someone else’s.
If depends how many people will actually live there. As someone else said, you could still have plenty of bathrooms with 4 and use the saved space for luxuries in the master bedroom such as dressing area and really luxurious large en-suite, this would be lovely to use but also gives a wow factor for re-sale to families, more than an extra tiny en-suite.
Different families would probably like different things….and even for them, what suits will probably change over time. A family bathroom though seems a standard thing in a house. It is a bit odd not to have one. Some people would consider it odd. People wouldn’t consider it off if there was only 4 en-suites or if 2 bedrooms shared a bathroom.