Given that I have designed and set up, from scratch, several systems along the lines you describe, I'm really not that likely to miss the point! The fact remains (this is personal experience, not just theorising) that it's not viable to have people using home computers, other than possibly just for occasional use. If people are woking at home regularly, the company then becomes responsible (effectively, even if not stated) for maintaining that home computer so that the person can work - and with some of the junk out there, that's a massive pain in the arse and can be very time consuming. The company is also (legally) responsible for workplace assessments to comply with health & safety responsiblites - and laptops do not generally meet this for anything other than occasional use, unless some combination of docking stations / monitors / USB keyboards & mice / laptop risers are used.
Then there is security. Keyloggers are one risk,but not the only one (and clicking on screen doesn't necessarily defeat all such malware). Many people will have no antivirus. They may be running out-of-support operating systems (particularly Windows 7), they may have all manner of dodgy junk installed on their computer. As I say, many companies have had to accept this as a short-term measure (around the beginning of April, business laptops were out of stock nearly everywhere), but it's not one which many will want to accept long-term.
As for using dumb terminals in place of desktops in offices, that can work in some circumstances but is not always suitable. If the back end consists of session-based terminal servers it's a lot less flexible than using standard desktops with software running locally - this is a significant downside. If a full VDI system is in use with individual VMs / customised images then it works better, but the underlying server infrastruture for that is considerably more expensive.