But I'm curious to know which countries have the highest taxes? And do you think there's a chance they will lower them in the future?
Your input would be greatly appreciated. Thank you very much.

I can mention all the countries who treat cryptocurrencies as assets subject to higher taxes compared to other financial assets. For example we have India, Japan, USA and also France and Germany. I can't find reliable sources for exact rates.
I can't speak for other countries but let me give you the exact numbers for India.
In our country 30% capital gains tax whether for short or long term with no offset against loss, along with that 1% TDS which is also a huge sum. For example If I sell $1000 worth of bitcoin then $10 will be deducted instantly that's flat rate whether I made a profit in that $1000 trade or not.
Higher tax rates is reducing the potential revenue for the governments, and need policy makes who need to understand this if we want to see the changes but as long as these old folks continue as leaders and just do what their central bank suggest will not lead to anything positive.
Honestly speacking, this is insanly high tax which can encourage people not to declare their gains and look for hidden options. In other hand, for a country like India which is not among the most taxable countries like Israel or Japan, I think India apply those high taxes as a way of fighting crypto wide adoption as much as possible.