The ProConti teams just aren't strong enough and guaranteeing wildcards to the two of them who were just relegated from the World Tour just means that there's essentially a 20-team World Tour and only two actual wildcards that the organisers have any discretion over. This is further devalued because the gaps in budget between the top two levels are getting ever higher and it's far better for most riders' careers, at least from an earning point of view, to be a domestique at a top team than a leader at a second tier team, because the second tier teams (other than those on the cusp of the World Tour or recent relegation candidates) are not strong enough that they can compete against the WT even in most smaller races, and the domestic calendars have been ravaged enough (plus the desperate hunt for UCI points in the battle to avoid relegation has meant WT teams take points off the PT teams there anyway) that they can't really offer the viable alternative that they used to.
Also, a few of their old revenue streams and ways of getting access to riders are being cut off; those contracts with Colombia or Venezuela that gave them a leg up on Latin American talent that was only being scouted by one or two teams at the higher level are now gone and successes of the Bernals, Carapazes and Higuitas of this world mean that everyone and their mother now scouts Andino cycling; plus there is no longer that steady stream of dopers and/or riders excommunicated from the top tier who they can rely on who have name value but come cheaper because of their dubious history - the likes of di Luca, Garzelli, Rebellin, Schumacher, Rasmussen, Santambrogio, Sella, Pellizotti and Riccò riding on those teams is a thing of the past. This year was the first time in a long time we had that possibility (and I guess in theory we still do), with López and Quintana both available, but it seems López prefers to smash all comers from the comfort of his own home rather than scrabble around for a lesser ride in Europe, while Quintana's asking price is too much for the likes of Burgos.