Cofidis have significant interests in the Spanish market and so want some relatively prominent Spanish riders. With Fernández and Lastra hardly leadership material at this stage, and the Izagirre brothers the wrong side of 35 and Herrada now 34 as well, it makes sense to spend out on a Spanish rider who is good in the kind of terrain that a load of those French 1.1 and 2.1 races are rife with.
As for Movistar, they've never had all that high a budget, they were never a top budget team, they just were very prominent due to having Valverde and having backed the right horse when picking Quintana out of Colombia - they used to be able to do well because fewer people were scouting Latin America for riders and then the collapse of the alternatives in the Spanish market left them essentially able to take their pick of anybody coming through the Spanish scene for a few years. They then made some questionable decisions like breaking the bank for Landa, and backing Mas as their main horse, a guy who, while he will get solid GC results, isn't going to be banking you many stage wins and consolation prizes on the way if his GC bid fails. They also got unlucky in a good few ways - they had Carlos Rodríguez coming in, before Brailsford realised the disaster Ineos' offseason was becoming, stepped back in and fought tooth and nail to keep him; they had a successful integration of Miguel Ángel López before he had an epic meltdown at the Vuelta and had to be traded away (in the end that was a bullet dodged, but it cost them a fair bit in terms of UCI points in the interim); Richard Carapaz was poached away from them before they had a chance to enter negotiations thanks to Acquadro's bad faith dealings (this caused then to also cease to deal with him for a period, which cost them many a good Latin American prospect as well); they had Igor Arrieta on lock, but then he looked elsewhere when turning pro after they fired his dad for being a terrible DS.
Meanwhile some mismanagement and some rather unimpressive development opportunities have meant a lot of talented young Spaniards tend to prefer to go elsewhere in the first instance before circling back to Abarcá later; meanwhile the fact riders like Abner González and Iván Romeo have been promoted direct from the amateur scene to Movistar while riders in the team's own feeder end up at Kern Pharma has meant that even the team's own internal feeder organisation is not as attractive to young talents, because if they back themselves and go well enough in an external amateur team, they're liable to get straight to the WT setup.
Plus I'm sure the budget for the women's team being increased may have also had an impact on the men's team's budget too. Annemiek van Vleuten likely wasn't particularly cheap and, though you would expect not as expensive as Annemiek, Liane Lippert probably wasn't either.