Obviously all advice is general and shouldn't be taken as...

Obviously all advice is general and shouldn't be taken as personal specific advice for anyone as it's not considering your own unique circumstances and needs.

... but if you are in a position to buy more shares during a full market drop, similar to covid, where the underlying strength of the companies are intact such that you believe they will be rebounding relatively soon then to have cash on hand to buy in then is the exact reason why the phrase "money is made in booms, wealth is made in busts" is true.

Personally, I don't sell assets that produce. I don't currently consider EMR one of those so in the event of a global crash I would consider moving money out of EMR and into something that in a couple of years will be back pumping out dividends near enough to current day but at half the price to buy in.

I have a longer term view with EMR though, to balance that above, that I believe will pivot EMR into being a producer in my portfolio and as such I have already bought in at the global crash level price.

If you're invested in companies that are heavily integrated into the social fabric and expectations of the community, such as the banks and various places people buy food, it would include services like electricity, gas, water if those were widely publicly traded too then should there be a collapse and the value of the money you have in those investments became zero - you have far, far bigger problems in your society and your cash money is probably worthless too.

So don't be afraid of the value of your shares dropping, that's an opportunity presenting itself. Keep a focus on what the companies you're invested in, and looking at investing in, are doing with the business fundamentals. Do they have plenty of work to continue? Is demand going to fluctuate? Is there a risk of other nations changing plans that reduces future demand? etc etc