Whilst I don't think there's much choice. There needs to be safeguards to ensure at least some kind of fairness.

A revenue based tax for multi nationals that trade in the UK but pay very little CT on profits generated here. Including online retailers.

Further increases to taxes levied on offshore property speculators

Also anti avoidance measures to ensure assets moved offshore since the start of 2020 are included in calculations.

Lots of assets are invisible to HMRC, your gold coin collection and the wine in your fridge. Financial assets like ISAs are easily accessible through requiring platforms to report based on NI numbers. The more you look into this, the more problematic it becomes, and this is why hardly any other countries do it. This report is floated in the media to see what traction it has, like many others before. Nobody should worry about it, it's a complete non runner.

But lots are visible or can be made visible such as house value, pension pots, NS&I holdings, ISAs, bank accounts. A gold coin collection will be noticed if you buy gold coins regularly. Wealth in the form of furniture, pictures and, dare I say it, bicycles, can be assessed through insurance companies. It may not be accessible now to HMRC but if the necessary legislation is in place, access can be gained.
Also bear in mind that a wealth tax is apparently politically popular. If any political party wished to gain power it could be worthwhile popping in their manifesto.

Do you keep wine in the fridge?

I agree there are difficulties but they are not insurmountable.
"How do you value a DC pension or a teacher's pension?"
This is relatively simple. You establish how much capital it would cost to obtain the income received by the recipient if they had an annuity, taking account of their gender, health and age.

"What happens if your house is your only asset and it's worth £2 million and you live on the state pension?"
The tax charge is held against your estate.

"If my shares decrease in value by 1% can I offset this against this new tax?"
Only if the fall takes you below the threshold on the operative date.

By the way, I've been in favour of a wealth tax for years. The Lib/Dems supported it or many even still support it.
The problem of course is that temporary measures have a habit of becoming permanent. Wasn't income tax supposed to be temporary to pay for the wars with France?

Can anyone actually imagine how such a tax could even be assessed and collected ?

The real wealth is in the hands of the very few - say assets exceeding £10M per head. These people already pay accountants to avoid them paying their due and rightful taxes - as do the international online corporates that plunder this country while paying effectively zero tax. These are the people you need to hit so how are you going to achieve it ?

For everyone else below the £10M personal assets how on earth could you fairly assess the value of all their assets - it is impossible. One has 0.5M in art work hanging on their walls, another a £200k classic car in the garage, anothers wife has £250k of jewellery, one has all their retirement income dependent on capital in ISAs, another gets a cosy civil service pension (which should be valued at 50-60*pension income, yet another owns a company valued how exactly ?

The whole thing would fall apart as soon as you tried to implement it. The papers would be full of Dominic Cummings getting off scott free, while some 70 year old lady struggling to pay care home fees gets told to pay up or go to jail.

We need a 2% or 3% internet tax on all non UK domiciled companies selling on the internet. And some way of hitting the super rich where it hurts. But since the super rich run everything that doesn’t happen.