The PP does Vox's work for them.
The way in which the People's Party (PP) has not only done nothing to stop its direct electoral competitor—Vox—but has actually helped its growth, is an unprecedented case. Or, at least, a rare one. The PP and its media allies normalized Vox as a political actor from the very first moment it appeared on the scene, before it had any representation in public institutions. Its first major public event, in October 2018 in Vistalegre, signified the definitive recognition of the new party within the Spanish political system. It was an interesting moment: while democratic politicians were being heavily persecuted by the state and criminalized in the eyes of the public, facing exile, imprisonment, and expropriation, the new Spanish far-right and nationalist party (there had been Ciudadanos before, which had already begun its decline) was quickly accepted as a political option as valid as any other.
That same year, 2018, the People's Party (PP) had lost power as a result of a successful no-confidence vote against all odds, and Pedro Sánchez had begun a presidency that many predicted would be short-lived. As it became clear that this was not the case, that Sánchez was demonstrating his now-famous resilience, and that his leadership was shifting towards center-left reformism, the PP developed a vindictive strategy that culminated in a single objective: to bring down "Sanchismo." And what is "Sanchismo"? According to the party's official line, "Sanchismo" is the concentration of all of Spain's ills, real or imagined, in a single person whom all decent Spaniards must detest with all their might. This includes him and all those who (as the PP's talking points state) "are keeping Sánchez in La Moncloa." In summary, the strategy that the PP was able to arrive at (along the way there have been three leaders: the failed one of Casado, the erratic one of Feijóo and the uncomfortable one of Ayuso) is a discourse of hate, concentrated in this case on the person who is the president of the government.
As is easy to understand, this has greatly helped Vox grow. The decisive step has been to establish governing alliances in many municipalities and several autonomous communities: in these agreements, whether Vox enters the government directly or "supports" it from the outside, the PP has been irrevocably beholden to the demands of the far right. This has been the case from the beginning in the Valencian Community and the Balearic Islands, for example, and it will be so—even more severely—in Extremadura and Aragon going forward. The dismantling of Sánchez's policies has undoubtedly eroded the PSOE and the left (which also has a strong capacity for self-destruction), but above all, it has led to the PP's subordination and surrender to Vox. Feijóo cannot even dream of a presidency—if he ever attains it—that is not controlled by Santiago Abascal.