Only IO can say for sure, but I highly doubt it. They were adding them in as featured contracts were released, but they stopped about a year ago. Having unlocks past that turns it into a slog for new players, some of whom aren’t all that interested in contracts mode to begin with.
It seems like most of the unlocks they’ve added in the last year or so have been through challenges added to levels or the Elusive Target Arcade instead, which makes them much more accessible.