Thanks /Kjell for the July 4, 2021 comments that Poland did not want to pay for 32 year old second hand Swedish Sodermanland submarnes.
In addition to the age and cost of the sub's Poland would probably wish to buy standard design subs from a fellow NATO ally rather the Sodermanland (which are effectively ophans/unique) from non-NATO Sweden.
Poland's limited defense budget migh also be committed to funding replacements for its 2 x 40 year old Oliver Hazard Perry class frigates. New frigate options include buying UK Type 31 frigates, maybe from other NATO allies or locally built. Replacement frigates would also likely have the Mk. 41 vertical launch silos capable of firing land attack missiles. Poland saw a need for a submarine based land attack cruise missile (SLCM) capability but if Poland's new frigates have this capability new submarines would be a lower priority acquisition.
Poland eventuallly buying subs from a NATO country (probably France or Germany) would strengthen the NATO alliance and serve as a concrete down payment on protection for Poland from the more powerful NATO countries, like the US, France, Germany or the UK.