Why has focal raised their prices so much on Sopra line

Inflation has increased over five years.  Shipping costs around the world have increased dramatically over the past year.  The cost of materials has also increased dramatically over the past year.  Inflation at 3% on 15k from five years ago would come out to about $17,300.  

That's not gouging, that is the world marketplace at the moment.  Sucks for us, including myself, who couldn't afford $15k back then, but could probably swing it now. 

I'd say, look at the materials being used in the Sopra line and see what has increased from five years ago.  That's probably the major difference.

The manufacturers don't want to increase prices, especially in this super-competitive hobby like audio equipment, so they know that they are losing customers because of the higher costs.  Sucks for everyone, really.   

I read an article or comment online so take that for what it is…. That they were priced cheaper over here to compete with domestic US brands.  
I think once they got a good reputation they adjusted that price to cover international costs and keep their profits roughly the same between regions.  
Keep in mind that different brands are very differently priced in different countries. Wilsons and Magicos are almost double the US price in Europe. 
Buy used or take a look (assuming you are in the us) to north American brands for a better deal. Revel, paradigm, legacy audio etc.  Just as good 1/2 the price. 

Supply & demand. They were $15k when they came to mkt. Now after they have sold their target #, they understand its popularity and peoples desire to own it. So, they raise the price.
Plus consider this. Sell 5 pr @ $15k= $75k. Sell 4 pr @ $19k =$76k. IOW, more profit. But they also have saved parts & labor on a pr of speakers. When people quit paying the price they will lower it. But they aren't in the business to lose $$$ either. It HAS TO make a profit to survive. So, it becomes a balancing act.