Sucks but a few reality checks are needed here:

1- Lula won in the North and Northeast regions with the support of the majority POC and poorest population there.

In the industrial/agricultural South and Southeast regions Bolsonaro won by another landslide 55-45, same as the first time btw.

The Brazilian congress is now also the most reactionary in decades. What exists of the Brazilian left was able to rally around Lula but that didn't translate into a general rally around the PT or other left candidates.

The western left must stop taking Lula's victory as any indication Brazil is turning left or as a reflection of the general population. At most it is a reflection of internal demographics and the remnants of the old ideological basis. This should be almost a sticky somewhere whenever people start discussing Brazil.

Brazilian neoliberalism destroyed the left in the urban centers but material conditions along with social differences including racism and discrimination made it harder for neoliberalism to change much in the other areas of the country. This only works as long as Lula is alive. Literally, I don't want to be a doomer but if you really want to know the subject of the post-Lula left is pretty sad and controversial.

Lula was a union leader and an industrial worker. The Brazilian left was built on this type of pro-union worker movements some of them behind the big state corporations Petrobras, the strength of which came from the rapid industrialization of the Southeast region.

Sadly though If you look back 20 years you'll find Lula's stronghold among industrial workers in SP is completely gone now with a couple of exceptions SP is entirely dominated by right wingers and neoliberals.

Also Alckmin as a VP is a hot subject, a neoliberal ghoul and one of his literal archenemies lol. Maybe it was necessary to rally and secure the capitalist class support, but it is certainly the mother of all deals with the devil.

2- Adelio Bispo, Bolsonaro's attacker was diagnosed as mentally ill, he didn't do it based on ideology or any leftist motivation.

I wont go into too much details but the subject of radicalization talked about by western leftists is as much taboo in Brazil as in the west. Carrying guns and doing an adventurism is strictly the realm of criminals and drug dealers, you are extremely guilty by association for advocating arming the working class. Besides Bolsonarism got there first anyway, advocating for relaxing gun control.

Yes this is also sadly in sharp contrast with movements such as the agrarian land reform movement which is pretty based and violent(the MST).