Let's get back...
While the ability to work from home as required is no doubt a boon to everyone, Mr Sunak is s right - as much as it pains me to say it.
In my 20+ years as a commercial developer (first desktop applications then web), I have lost count of the amount of problems that have been solved by "water cooler" conversations - just that off-the-cuff conversation with a colleague over a coffee (and thus away from keyboard) provided the alternative approach that had not been thought of, and the issue resolved.
Expanding this out logically - team-wide design sessions, while possible with online tooling, certainly do not have the vibrancy and out-of-the-box thinking that their in-person counterparts do, plus anyone can wield a whiteboard marker or post-its (as opposed to having to create accounts with x/y/z software then figure out its particular quirks). Mentoring and pair programming - again, possible online but vastly ineffective compared to having two people at one machine.
Working remotely also puts us in the worst of both worlds when it comes to focus and getting assistance: pre-lockdown, if someone was at their desk with their headphones on, I could see this and know to go bother someone else with my question, thereby not breaking their concentration. If I had a quid for every time I'd received some kind of chat message notification expecting a response when I was in the middle of some tricky piece of coding (this but ten times worse), regardless of my "do not disturb" status... similarly, if I needed a hand with something, I could go and see if someone was around, wait if they were in the middle of something else (thereby avoiding breaking their concentration until they were ready) and talk through the problem... again, if I had a quid for every time I'd posted a request for help only to get a bunch of people pointing me at stack overflow links and not actually discussing the details of the issue...
Then (and this is the web developer coming out in me) there's the whole "security" chestnut. How many stories have we seen on here about compromised routers? Of course, there are steps that can be taken from as simple as changing the default password through to VPNs and the like, but the simple fact is that working in an office, it is a lot easier for security to be controlled by a professional whose job it is to do just that than it is for a whole bunch of home-based connections each being administered by the individual employee, who almost always not an IT/networking professional. Remember, it only takes on weak point for a data breach and the company being slapped with a massive fine...
And this is before we come to the whole question of work-life balance and tha sort of thing - which has been covered by many others, so I'm not going to re-tread that ground - except to say that while individual productivity may be similar from home as in the office, it has been noted that team productivity is down by anything up to 40% (there was an article on ZDNet a while back but I can't find the link right now) due to lack of collaboration between team members.
I get that the commute is a pain in the ass (personally, I can live with it as it creates a nice buffer between "work" and "home"). And sure, working from home is great when you do have something happening that you need to be around for, or when you just want to get on with something (assuming you're allowed to switch off that messenger app). But ultimately, for any team to function optimally, there needs to be face-to-face contact - and that requires a central location.