Interestingly enough, even The Guardian: Here does not appear to be blaming this on Brexit. The only mention of Brexit comes at the end of the article:
This latest shipyard closure underscores a wider British failure from the 1980s on. End of empire need not have meant an end of British shipbuilding. But it was allowed to happen. Tough, government-led decisions to target new commercial shipping markets for fishing vessels, ferries and cruise ships were never taken. Governments focused instead on naval needs alone; R&D defaulted to the defence agenda. The result is that a post-Brexit Britain would have no shipbuilding sector adapted to 21st-century markets. Instead, it would be closed for business.


And the comment in the last post: Harland and Woolf about to go into receivership - another British Industry It is not a "British industry" the Guardian makes it clear that the business is Norwegian owned.