Dreadnought cost 1,783,883. The average cost of the Invincible class was £1,655,197.
The average cost of Lord Nelson and Agamemnon the last British pre-dreadnoughts was £1,541,443 about £250,000 less.
The average cost of the 3 Minotaur class the last British armoured cruisers was £1,396,154 about £250,000 less than the average for the Invincible class.
Fine then, decided those damnable French were out to steal the holy grail with their Jeune École thinking and their dastardly submarine fleet, and went bonkers on destroyers to the tune of £1,000,000 leaving insufficient funding for Dreadnought
The practicality of the UK not building Dreadnought in 1906, nor the Germany's slipway capacity, or constrictions of the Kiel Canal are not really the primary point. This isn't an AHC, plausibility check, or planned timeline, purely hypothetical.
Hypothetically, if all of the British government drowned themselves in the Thames and a new government was seemlessly put in place using the combined power of The Force, hippie ideals of free love, and Captain Planet, only this one was hostile to Dreadnought. In her place the government spent £1,800,000 on cruise ships with gun turrets that are only capable of firing confetti and glitter, and then attempt to sink Ireland via ramming, and nothing else happens.
Suppose this happens, what would be the political (ie everyone giving Germany the stink eye) ramifications of Germany lunching the first dreadnought.