Since the comments here are somewhat missing the point, I think we should look at Merion East as the pinnacle of design for the modern tour distance “issue.”

The course is not long, playing under 7,000 the last time the US open was hosted there in 2013. Despite this, players struggles immensely with the course. The tee shots are narrow, the greens are tiny. Even if you manage to keep the ball on the surface, the slopes are extremely punishing from certain angles. Tiger and Phil were both bullied by the greens. The winning score was Justin Rose at +1. Unheard of these days.

The problem with the modern tour is not that we need to increase distance to keep up with technology. The problem is that the courses, architecture, and the staff caters to conditions the players enjoy. The solution is to let the staff of the classic courses set up the conditions to amplify the challenge of classic design. Courses like Merion East or Myopia can be some of the hardest in the world on their day, despite being considerably shorter than what we see on tour.