I meant something else(will go on more detail down below). Also, 'on the verge of collapsing' may be a bit too much, but...
PT had a plan for the economy in the 2023-26 period: do the same things they did in the 2003-08 one. This means: an overvalued Real, lower interest rates, easy credit for people, which leads to people buying new cars, refrigerators, TVs, and so on, stimulating economic growth through a major increase in consumption. With a better material situation, popularity of the current government rises, and the increased economic growth means there's more money for all the gimmies going around.
There's one big problem with that: overall conditions are not the same as they were back in 2003. Interest rates are not going down; Brazilian industry was savaged by the Chinese one, puting Brazil back in the condition of an exporter of agricultural products; the retail sector, a crucial part of PT's plan, is in the early phases of a meltdown. PT will not be able to enact its plan. It will be forced to rely on the agricultural sector and increased taxation to generate revenue for all the gimmies needed for the system to work. This increased taxation will have negative effects on the economy.
As a result, people will be dissatisfied(to say the least) with the current government. And now we come to what I really meant: you can't impeach a president without him/her/it tanking on popular approval before. Both impeached presidents had less than 15% approval rates(I think both were around 9-12% approval). Bolsonaro wasn't impeached , even with the press slinging shit on him 24-7, because he had a lockdown on enough voters(IIRC, he never got below 25% approval, and usually was at 30-40%) to make it unviable. Lula wasn't impeached at the Mensalão mainly because his popularity was high. So was FHC, in his first term(and in his second, he had Antônio Carlos Magalhães riding herd on Congress to bend it to his will - the only president since 1988 who managed to do that). The easiest way to tank a president's popularity is by having a recession. Therefore, the economy has to tank more than it's doing now for him to be open to impeachment threats.