And honestly, if the intention is for children of younger child of the monarch to be only addressed as children of Duke/earl/whatever going forward, then issue a LP and make it equal for everyone in that situation. Otherwise, how is THAT not hypocritical?
I believe that that is what the Queen believes will happen - but not while any of her HRH cousins, who with one exception have been working royals for most of their adult lives.
To issue such LPs now would mean the Duke of Kent, aged 83 for instance would be stripped of that HRH he has held all his life.
The start is the way Edward's children were stripped of the HRH - by making known The Queen's Will.
By saying nothing now for Harry's children they will be born in the same way as Edward's - the children of a peer of the realm.
They will then issue a statement to say they will stay that way when Charles becomes King - so again using 'the monarch's will'.
When all the current HRHs who are cousins of The Queen have passed then they will issue the LPs and Beatrice and Eugenie will lose HRH.
Remember too that under the existing LPs Louis's children will be automatically HRH while Charlotte, who is ahead of him in the line of succession, won't - a perfect reason for new LPs but now for another 20 or so years.
If Harry's children have HRH then though it could be much harder to do it and the pressure will be for Charlotte's children and thus all girls children to be HRHs ... which could be interesting as Anne's children will only be in their 50s so suddenly we have the situation where Peter becomes an HRH or Earl Snowdon - equally the female line grandchild of a monarch.
They could so easily solve this problem by issuing LPs stating that only the heir apparent's children, in each generation, born on, or after 1st January 2001 will be HRH. That would allow those born before that date to keep it and only William's born after would hold it instead of the pig's breakfast they are creating by not doing something.