The Queen has more power over British law than we thought

This is always a fun start to any argument about the constitution of the UK.

The thing is, you're building on a foundation that could potentially be challenged. As we discovered during the Brexit debates, people are happy to use words like "parliamentary sovereignty" when it suits their purposes, yet clearly many of them have never actually read Dicey, much less understood its entire argument or what the resulting concept of parliamentary sovereignty really means. And of course Dicey himself was not empowered with any special authority, but rather assembled a rational argument based primarily on historical precedent, which has subsequently been broadly accepted by figures in authority in the UK but is still, like everything else about our constitution, more a matter of convention than clear popular mandate.

Perhaps more importantly, if Parliament really is constitutionally sovereign, in the sense that its rules are supreme over all others and nothing a current parliament does can ever bind a future parliament, then we can never improve our system of government by adopting a formal written constitution, even if doing so would have overwhelming public support at the time. If you're going to make any argument about improving the constitution, starting from a foundation that necessarily precludes the single most important improvement that could be made might not be the best idea.

So the Queen's advisers lobbied for a royal commission to not be possible to scrap by executive order (but it was scrapped anyway), for the royal estates to be exempt from road traffic regulation (all private land is) and some Queen's Estate representatives threatened to complain to a senior minister in a meeting with civil servants about the impact of a bill which the Queen gave assent to anyway. Over the space of half a century. If there are other instances where royal representatives were a roadblock rather than on of many special interests whose opinion they humour, the incentives for politicians to publicise them are strong.

I think that's more consistent with the monarch's impact being "practically nil" than her being the reason things never go people's way. There's an argument that's more legislative discussion than the representatives of a ceremonial monarch should be participating in, but you don't pressure civil servants by threatening to tell the Chancellor you're gravely concerned if you're actually pulling the strings.

The fact that governments have sought her approval on matters, despite not being required to do so, isn't remotely surprising. And if you didn't care about the state providing a privileged life for the royals before, why would you care now?

The fact is, not enough people care enough to make it a political priority.