@Kai Nemo Firstly, I don't agree with your conformist statement that "IRCC is intelligent enough to know which applicants should be given priority". It's a well established fact that IRCC like all monopolistic immigration authorities is a highly bureaucratic and flawed organization. And lot of their decisions are driven by politicians' policies and laws. For example as per IRCC Spousal Visas processing time was 2-3+ years, meaning newly married spouses were seperated for 2-3+ years till their visas got approved. However, spousal visa applicants teamed-up and hired top-lawyers who petitioned to have their Spousal Visas expedited. As a result, the immigration committee passed a ruling to priortize Spousal Visas. Now Spousal Visas are being processed on highest priority.
Now coming to your question on estimated time. As much as we would like to believe that it's computed by some smart AI, but reality is that there is no absolute maths going behind these estimates. These are pure estimates based on the fact that on average processing time during normal times was 12-16 months, so they are assuming that when a new application is submitted and things are back to normal then it will take 12-16 months. However, if you applied in 2020 then add those 18 months of delay and it becomes 33 months.
To give another perspective, if you were to apply today, you would think that it would take you 12-16 months as per estimates. However, after you have applied tomorrow your estimate will change to 33 months
Reason being, they don't know when they are going to start processing the SUV applications. So these estimates have no realistic value, except telling us not to expect anything anytime soon.
Another example - if you know someone who has applied in Express Entry there is a progress bar which gives percentage of progress of your application. IRCC has disclosed that it's based on hard-coded numbers, so for example for all applicants after 3 months it will change to "Background Check Passed", whereas in reality there files might not have moved one-bit. So much for smart IRCC!
So long story short - SUV estimated timeline are very speculative and are based on when they think they will restart processing SUV applications. At this time, there is no clear visibility on that as SUV is still not a priority for them. Hence SUV PR timeline has recently increased from 30-32 months to 33 months. Every month it gets delayed it will keep getting pushed back. The optimist in me thinks that the day they start processing they might double-down and clear all applications one-way or another in 3-6 months. But at this point it's just wishful thinking and hoping that our startup can survive till that time and any pivot doesn't mean having to reapply with a new idea.