While I agree the sentiment is a bit over the top it can be argued there is some truth in it.
Labour (and others) went for the broad stroke of policies rather than one issue. They went with trying to explain why these things would be good whereas what the Tories wanted wouldn't be. Trouble with this is it can come across as condescending and smarmy.
Tories went with KISS. Just make it one issue as much as possible and everything else keep as basic and vague as possible. Repeat the same old short catchphrase over and over. Put out disinformation and smears and assume people won't check. Distract people to negate negative press by the same means. They treated people like they were stupid, they were just clever enough to not let that view slip out(or at least not very often and if they do, like JRM, you get sidelined). Look at the huge majority they got with these tactics.
Labour/lefties get worked up and emotional because they genuinely care about improving things, hence at times the frustration resulting in derogatory language. Conservatives are (on the whole) more concerned about the effect on themselves and if there is benefit to others they can use as leverage even better. If it makes people's lives worse, keep it hidden.
If it was the other way round and we had a system more akin to the Scandinavian model where the likes of Conservatives wouldn't have the same influence and thus able to run the system to their own benefit like they do here do you not think they wouldn't get frustrated and call people stupid. Look at some of the billionnaires who very quickly result to insults when a board prevents them from doing something they want.
This is our 2016 Trump-Clinton moment. Clinton was more progressive and tried to explain her policies but came across as arrogant and smarmy. Trump went with a catchy slogan, entertain the masses at rallies and just make false claims about others that you assume people won't check.
This is a potentially dangerous trend for the future.