Proof coins were orginally intended to be the best possible examples of coins struck off new dies, to be kept as a record.
AS such, I would suspect that the earliest Canadian proof coins go back to the beginning of homeland struck Canadian coinage, like every other country that has a history of national coin production.
The modern examples of such coins struck for the collector market would be known as 'specimen strikes'.
It was realised that such rare coins have great numismatic significance, and when they come up for auction, could command very handsome prices.
Modern proof coins are very different.
They are far more common than the proof coins of past times, that were struck for record purposes only.
They are made in much larger numbers for commercial reasons, to be sold to the collector market. They are made from specially prepared polished blanks, and struck from specially prepared dies, with the fields polished and the raised details cameoed to a frosted appeareance.
The frosted details are usually obtained by laser etching. The work in the past was done by preferentially sandblasting the details or preferential acid etching.
Unfortunately, some of the very fine detail has to be lost to obtain the cameo effect no matter what method is used.
I have seen some considersble loss of detail in the cameo areas of some modern proof coins. Laser etching seem to be the least deleterious.
The DMPL effdect seen on the best examples of
Morgan dollars is the result of the first strikes off fresh new dies. For this reason these coins, if they have never circulated, are also very rare, and also command very big prices at auction.
These coins are NOT made from polished blanks, struck from specially prepared dies.
Modern NCLT proof coins are usually made in as large as numbers as possible according to an artificilly selected issue price, to maximise profit vs the number issued into the collector market.
The artwork and packaging is usually of a very high standard to appeal to the collector.
Proof issues of 100 years ago did not look like modern proofs, and did not have the advantage of specialized artwork or attractive packaging, because that was never intended. They were never intended to be sold in commercial quanties for a profit. As such, they are very rare.