'Poor' is not usually considered an expression of 'compassion' in most contexts, certainly not on HN.
Are you learning English? If so, it's best to follow the dictionary meaning and examples.
For example, when HN users write 'poor engineer', 'poor dev', 'poor software', 'poor working environment', 'poor commute', etc... they most likely don't intend to attach any connotation of compassion.
I think most readers will interpret 'poor suckers' literally as in 'suckers' who are lacking wealth/income/means/etc...