Hi Woodelf.
Firstly, please accept my apologies for not replying to your email some time ago. It was on my 'to do' list for a while but then dropped off my radar.
It's Government policy that everyone should have a smart meter installed in their home. See here, on the Gov.uk website:
https://www.gov.uk/guidance/smart-meters-how-they-work
So one can hardly blame energy suppliers for trying to get everyone to have them.
Personally, I've got absolutely no objection to them in principle but I know that, after they've installed any type of new gas meter, the fitters have to test the gas appliances in the home. I also know that my 30-year-old gas cooker wouldn't pass the safety test because two of the rings emit too march carbon monoxide. (I simply don't use those rings anyway, and keep my carbon monoxide detector in good order, so I'm not actually in any danger). However the fitters would be forced to disconnect my cooker, leaving me with a hefty bill for a new one. So I simply ignore the countless emails I get telling me that British Gas urgently need to replace my gas and electricity meters.
Unless, unusually, you've got any similar problems though, I can't think of any reason why you shouldn't allow SSE/OVO to go ahead with installing a smart meter in your flat.