The situation is not totally clear yet, some brokers still allow you to buy US ETFs, other brokers have implemented a buy lock on those ETFs.
We have to see how it will develop. Indeed a position in BRK is now more attractive; BRK is not a packaged product like an ETF according to the rules.
A concern is the increasing tendency for US funds to simply opt for "prohibit marketing to EU residents" due to such EU regulation. Conceptually as things currently stand its just a badge, little different to other pathetic EU regulations such as having to tick to accept browser cookies (mostly just mad EU style bureaucrazy). KID formats are a lot simpler than KIID's and could be knocked out by point of sale (brokers) themselves relatively easy so as to be compliant.
UK FT250 index tracker funds will be interesting as that index also includes a number of Investment Trust stocks, so conceptually a index fund needs to provide a KID also. Personally I'd be more inclined as per many towards EU rules (laughable) and would simply add a mandatory I've read the KID tickbox to open up access to trade a fund and deadlink the associated KID link, so if contested you could say that the investor had confirmed they'd read the KID before they'd traded. And if anyone did ask about the KID deadlink just say we're working on it and check back again some time later.
4 out of the 31 countries leaving the EU (Brexit), 25% of the net contributors to the EU, 50% of EU external exports are via the UK. 16% smaller EU population. With no deal Ireland and Spain could see massive economic negatives. Slap 50% tariffs on German exports to the UK as well I'd say. Its not interested in economics, just continuation/expansion of German political dominance of Europe (otherwise artificially low Mark and able to sell things to other EU member states by adding it to their 'debt' that will never be repaid but that Germany has disproportionately distanced itself from (ECB liabilities)).
Thing that finished it for me was free-movement of people EU policies when the likes of Germany bilaterally opened up the floodgates and 'fast tracked' 1 million migrants - only to see a little while later that they had no idea of the whereabouts of 60% of those migrants.