Seems to be a Lot of confusion on here,
So what was said is you can leave your home for four reasons.
Listed in this document.
assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/874738/Full_guidance_on_staying_at_home_and_away_from_others.pdf
He is closing retail and hospitality with some notable exceptions. Listed in this document.
assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/874732/230320_-Revised_guidance_note-_finalVF.pdf
What he didn’t say is you can only go to work if your work is “essential” or you’re a key worker. He did not say he is shutting offices and factories, he specifically stated and the government website confirms you can go to work when your work absolutely cannot be done from home.
As such, unless retail or hospitality as listed in the document, all other work places can remain open, and workers can go to work. The work places have to maintain a protocol of social distancing when operational and keep employees six foot apart.