That depends on where some investments are held.
And don't forget the very generous tax relief on contributions going into pension schemes and the tax free element coming out. All of which have grown CGT free over the decades.
If you plan early enough and you can get your head around giving away the stuff you don't need when you are youngish, with no reservation of benefit, you can mitigate reasonable chunks of IHT (at the moment of course ... more than likely to change no doubt)
Do plenty of Skiing too boot to make sure you are not the richest person in the graveyard... such a waste.
You can give monthly sums away of any amount provided it is out of normal income and doesn't lower your own living standards or eat into your existing estate.
It's all swings and roundabouts at the end of the day.
What is it that you say, numbers and spreadsheets

Death and Taxes.....
Plenty of ways to navigate the problem.