There isn't really a limitation to the conversion of FAA CPL to TCCA CPL.
For most pilots, you would be correct. - there are no limitations to consider for the average American pilot, other than the IR requirements you describe.
However, many pilots on both sides of the border often see that there is a conversion process in place and they stop their research there. They don’t go on to see that the limitations for FAA to TC include no conversion for any qualifications not listed in the AC, an FAA license issued on the basis of another ICAO license, temporary FAA licences and certificates, a licence under suspension, a licence that does not have English language proficiency already listed, or that to even begin the process, the pilot must already have an appropriate TCCA medical completed.
While these are minor considerations for most, they are nevertheless limitations..