So just to add to NW5-flat’s point, the freeholder doesn’t take on unlimited liabilities because that wouldn’t be sustainable as buildings do age and wear. The lease clearly states that leaseholders will have to pay for these things and that is a fact of life with any leasehold purchase (which should have hopefully been evident from the bundle of paperwork you received as part of the leasehold buying process).
What the freehold will do is coordinate with other people in the block (both tenants and leaseholders) to produce a “reasonable” outcome. For better or for worse, they are allowed to charge for this service (“management charge”) and this is set out in the lease too.