It's not just big companies it's the choice of consumers
If you look around at your High Street there are mass fast food chains, coffee shop chains and big store chains
It's the consumers that chose to destroy small businesses in favor of convenience and cheaper products
It's why if you bring supermarkets to towns it destroys the local small business communities
There needs to be a massive culture change to reverse this
As for online great natural monopolies because if you want to go on social media you go to Facebook, X or Instagram
You are not going to bother with other services
Same goes for shopping as well