To be clear, approval for and grant of citizenship is in NO way contingent on employment. An individual who has relied on government assistance is no less qualified for citizenship than someone who consistently works in a high-paying job.
This is one of those areas in which causation and correlation are not much connected. It's like recognizing that almost all murderers drank milk as a child . . . does not mean drinking milk as a child has anything to do with becoming a murdered.
Work history is not an important factor because it shows the applicant was working. It is important because of what it shows about where the applicant has been living. The applicant with a regular job involving showing up at a known worksite in Canada, for a readily recognized employer in Canada, has an advantage because that is very strong, compelling evidence the applicant has been IN Canada. In contrast, there may be an open question about what an applicant with a sketchy work history was doing during extensive periods of time, and whether they were outside Canada for some of that time.
For example, applicants who are self-employed, or engaged as "consultants," can encounter elevated scrutiny compared to those employed by known Canadian employers. Not because employment with known employers is preferred, but because for the self-employed, and somewhat similarly those engaged as consultants, it is less certain where the individual has been physically located.
Even though the applicant with little job history might encounter elevated scrutiny and lengthy delays due to non-routine investigation, which during the last several years tends to result in really, really long delays (remember, when most applicants are suffering from long processing times, as they have been these past three years, the delays are disproportionately far greater for those tangled in non-routine processing), if they are qualified, if they meet the requirements, they will be approved and scheduled for the oath.