Except Umtiti, we usually always pay crazy prices though. I dont think the days of smart buys are over to be honest. The price of Inigo was for his many years of la liga experience, unlike Lenglet. What would Benjamin Pavard from Stuttgart cost us? He's a similar type of player. A good season for Stuttgart and being rewarded with a World Cup spot for France. If Lenglet ends up costing us 40-45m euros, it seems like a far higher price than what someone like Pavard would cost us.
Oh I agree Pavard would have been a great shout but by the looks it Valverde wanted a CB who has some La Liga experience and they decided Lenglet will be that guy despite his young age.
As for Inigo Martinez 32 Million for him vs 38 Million for Lenglet, out of the two I would go for Lenglet no question. Inigo Martinez has a lot of experience but I consider him more or less a more refined Bartra, great player with the ball at his feet but nothing more than an average defender that turns 27 this year and has no upside whatsoever.
At least with Lenglet, he's shown a lot of talent and he's only 22 years old who potentially has a better resale value down the line than someone like Martinez.