They definitely have enough capital for nuclear. Their neighbours, Slovakia and Czechia, both have quite significant nuclear installations. Czechia generates 34% [1] of electricity from nuclear and Slovakia 52% [2]. Slovakia is finishing expansion of one of their nuclear power plants (Mochovce), which will add 2 more reactors - each with ability to deliver 13% of total country consumption [3].

Both Slovakia and Czechia are bit more "richer" than Poland (if you look at GDP (PPP) per capita), however Poland is much bigger economy - 5x size of Slovakia.

My guess is that because so far they had so much coal (largest reserves in Europe [4]), it was no brainer for them. However they are now in the process of commissioning nuclear power plant and plan to generate power from nuclear by 2033 [4]

[1] https://cs.wikipedia.org/wiki/Energetika_v_Česku#Výroba_elek... (second row - Jadro - is nuclear)

[2] https://en.wikipedia.org/wiki/Nuclear_energy_in_Slovakia

[3] https://www.seas.sk/mochovce-3-4-npp

[4] https://www.world-nuclear.org/information-library/country-pr...