Working in Canada in no way guarantees PR especially for working for a few years. There are people who have lived in Canada for a long period of time on WPs Or have worked for decades as illegal immigrants. Immigration is a huge balancing act and a selfish process for the home country. Canada is really trying to secure immigration from immigrants that can help the Canadian economy and fill the labour shortages in specific industries, provide employees in lower paying jobs and attracting higher skilled workers in the hopes of growing the economy and innovating. Realistically Canada isn’t concerned about all workers getting PR. May sound harsh but that’s the truth. Canada has already made getting PR quite easy compared to many countries. During Covid it became too easy to get PR so students didn‘t have to finish their studies and you get PR soon after arrival in Canada. This would would not work longterm. Sean Fraser even said that this would result in too many people applying for PR in Canada and therefore having to cut back on spousal sponsorship, economic immigration from abroad, etc.