Lots of fun conspiracy theories flying around tonight but in all reality the reduction in population would not be worth the price the world will have to pay.
I would imagine it is almost inevitable that the world will go into recession by the time this is over and the longer it takes to get this virus under control the worse it will be. Millions will be unemployed around the world (remember the virus is killing people past retirement age so no jobs being freed up - sorry, I know that sounds harsh) which will lead to increased poverty, increased crime, poor health etc etc.
Here in the UK I think it is possible the death of the high street will be accelerated if a likely lock down goes on too long as retailers and coffee houses go out of business.
In a lot of ways our government will face a much harder challenge than their current one - how to get our country working again as quickly as possible.