Not sure why the media has gone into hysteria around smart meters, it has its flaws, but I've found it quite useful.
I've had one for 3 years now and happy with it. Does what it says on the tin. Gives meter readings and let's me know when I've left the gas on... which has been useful on two occasions. One when the gas boiler got stuck on (timer broke) and the other when the oven started leaking. Now true, I would have found both at some point... and not necessarily the selling points the energy companies were going for...
It also lets me know when the tumble dryer has finished, as it is in the out house, saves me make unnecessary trips in the rain in winter!
The two flaws the Government made upfront, was not standardising the physical meters (make it easy to change suppliers) and trying to make it compulsory/push targets which has driven this you must have a smart meter. For some it will work, for others it won't.
As for saving money, I probably have changed my habits around leaving the heating on all day (there was a clear benefit of using the timer), leaving the oven on for extended periods and the use of various electrical appliances. Probably one-off hits, but I worked out it saved me around £50/annum from typical £500/annum (with recent price hikes that's probably been wiped out!)
...and thank goodness I no longer have to crawl into the cupboard with a flashlight to get a reading to correct yet another bonkers estimated bill based on the duckworth-lewis method of energy usage... I'm building a model steelworks, not a lifesize replica...