1. Your link actually shows that 74% (now 73% as of the latest data) of Canadian diary barns (without robots) are tie-stall. That does not necessarily imply that the cows are kept in tie-stalls. When we still had cows in a tie-stall barn they were only tied during milking.
2. Nobody is realistically building new tie-stall barns. Especially in Canada where the law now makes that impractical (not completely impossible, but for all intents and purposes). Those that still exist are overwhelmingly old and therefore small. Despite tie-stall barns being most prevalent by a tidy margin, the same dataset again indicates that only 35% of the cows are in tie-stall barns. How many of them are kept in tie-stalls is, unfortunately, not enumerated in the data.