Generally speaking, the market is flooded with poor quality employers offering less than the going rate, competing against and undermining the better employers with better offers.
It is also state economic policy to create a large reserve army of labour in almost all occupations, meaning that there are slightly fewer jobs to go around than candidates available, there is constant churn between employment and unemployment (or “enshittification” of good jobs into poor jobs), and a massive unemployment risk is shifted to workers for the benefit of employers collectively who are enabled more easily to attack wages.
Under these circumstances, if you’re unemployed and have a crap job offer in hand, it’s best to just take the crap job, and then immediately continue looking for better, and then leave the crap job if the better offer arrives.
This transfers the risk and costs back to the employers, and the sting which a fast turnover gives to the crap employer, is typically far more than any surplus value they extract out of you in the short time you are present under poorer pay and conditions than the better job you are moving to almost straight away.
As well as insuring your income in the meantime, this sting helps undermine the competitiveness of the poorer employers, and therefore supports the better employers whose jobs you want to move to.