In most cities you can not make 20 mph most of the day, due to too many cars.
So if the new rules stop cars coming in, you might be able to make it to the speed limit.
But for a safe city, get all people to cycle and that can only be done if the city gets much more safe than any UK city is at the moment.
20 mph is quite fast enough in urban areas - it should be the general speed limit in all residential areas and in town and city centres. Far too many people are still being killed by drivers who think they are more important than pedestrians and cyclists.
The council aren't forgetting delivery traffic; but cyclists are a lot more vulnerable to bad drivers than drivers are to bad cyclists (one can and will kill another; it doesn't really happen the other way)
I live near Edinburgh and drive in Edinburgh - delivery drivers have to accept the changes.
Get used to it!
btw you did not ask a question.
Hoots man - ban the cyclists!