I’ve just checked the size of mine off the back of this thread. 106m square.
We still have 3 double bedrooms, one single, utility room, sitting room, family bathroom, downstairs loo, biggish open plan kitchen/dining room leading into to a smaller second sitting room.
5 of us, me and dh, 23 year old ds (who has the downstairs bedroom converted from a garage, so has his own space with sofa in), 11 year old and 5 year old with their own rooms - albeit, the 5 year olds room is a box room, but the second sitting room is more of a playroom set up at the moment, so it doesn’t matter.
We never feel cramped in this house and all have enough space, we have some pretty great parties in this house too. It’s a great size for us.
We wouldn’t need double this size. We did look at moving a while ago, and most bigger houses, it was all more space as in en suites to 3 of the bedrooms, while nice to have, not essential and a double fourth bedroom. I like our house as we have two sitting rooms.
We also looked at moving to a better area, but the house would have been a lot smaller (Victorian terraces with 3 beds, the younger two would have had to share), but we decided to stay put here, cheap mortgage.
That said, if you want a bigger house, then go for it.
Life is short. I wouldn’t be thinking value future downsizing, tomorrow isn’t guaranteed anyway, you have no idea what will happen.