Not strictly so about services only being once an hour in those old days. I've got a copy of the 1990 timetable in front of me, and the old Cross Country timetables are very interesting and varied compared to todays "clock face" like timetable.
Just as a rough guide. On a Saturday back then, there were departures from Bristol Temple Meads to Birmingham and the north at 0312(!!), 0612, 0810, 0832, 0920, 0933, 1045, 1112, 1137, 1146, 1202, 1223, 1237, 1306, 1318, 1335, 1502, 1534, 1616, 1624, 1635, 1701, 1716, 1801, 1816, 1900, 1920, 1935, 2043, and 2203. Notice then that at some points there were services departing just EIGHT minutes after the previous service. And at some parts of the days there were gaps of an hour or so between services. Also some services running non-stop between Bristol and Birmingham too. Would this sort of timetable help ease over-crowding on todays Cross Country services? It could do. Unfortunately I don't think we're ever likely to see such timetables on Cross Country services again. As most train operators nowadays want a "clock face" like timetable to make it easier for passengers. But we managed OK with such timetables as those mentioned above back in those old days didn't we?