Why a patrol corvette may not need 40 knots

Should modern corvettes reach speeds in the high 30-knot range to keep up with intercept craft?

Only if the mission genuinely requires it; otherwise endurance, aviation, boats, and payload are likely better uses of displacement.

Speed is a mission-driven tradeoff rather than an automatic virtue. Machinery for sustained speeds in the high 30-knot range consumes hull volume, weight, fuel, and money. A patrol corvette can let embarked boats or a helicopter conduct the final interception while the parent ship preserves endurance and useful payload. The Littoral Combat Ship warns against sacrificing too much for a speed requirement whose operational purpose is unclear.