In the ideal scenario, if someone has education gap due to a job then the proposed study should match with the work experience to show progression. Getting study visa is still difficult for the ideal situation as you have to justify in your SOP on all the parameters like career progression, funds, country ties, why Canada etc. Now, when you think of doing a course which is irrelevant to your work experience and in line with your study which you completed many years back, this further reduces your chances and convincing Visa officer is quite tough which can be made possible only by writing a very strong SOP. At the end, I would say it is not impossible and it depends how you are able to show progression and convince the Visa officer.