Record companies in Britain freely agreed to a 50 year copyright term, back in the 1950s - they were doing well with new releases and current artists and couldn't imagine that anyone would be interested in stuff made in the 1900s....
Now, of course, the perspective is different particularly given that none of them are ever likely to own the rights to 'talent' that will earn like the Beatles, the Stones, Dylan, Elvis etc etc , in the future.
Whether they will bother about old recordings may be doubtful:
When I ran the Smithsonian label in the 90s I created a boxed Blues set that was very successful - to the extent that someone produced a knock-off - even down to the color and design of the box. The material on our set was licensed through SONY and I ascertained from Business Affairs that the other set was a bootleg. It contained recordings owned by many companies including SONY, and even some stuff that was not even PD in Europe. (The set was produced and manufactured in the US) Eventually the Head of Business Affairs at SONY told me that they would be taking no action - 'it wouldn't be worth the expense'
They may have sent a 'cease and desist' letter, I can't remember, but the set was out there and continued to sell at half the price of ours for a long time. I may be whistling in the dark but I can't really see the majors getting heavy over some 1925 recordings by Ladd's Black Aces, ferinstance. (Actually they don't even know what they might purport to own.) It would however be nice if legislation included a performance clause. If, after a agreed length of time, they choose not to reissue something then others would be free to do so.