The office was a typical 1960s bombsite-replacement 8-storey block, now replaced again by a City high-rise. We all (well, the professional staff) had company cars, which doubtless made a difference. Not infrequently we would suddenly need to head off to another non-City location within the day. If I came back with a client in the day with no spaces left there was a multi-storey over the road, cost was not ruinous.
Colleague in a Victoria office had no parking there, lived in Godstone (the town, which is nowhere near the eponymous station), drove daily to Brixton, parked in a side street all day, last bit on the Victoria Line. Parking restrictions in centre only, up to the 1990s, all came off at 6.30pm everywhere and at weekends, whereupon it was free range. Living in Canary Wharf, if shopping in Oxford Street would drive there on Saturdays. It's one thing to go by yourself, different matter with family, small children and pushchair. I guess Broad Street never had lifts down to the ground.
Probably about 50-50 between driving and rail commuting. You could have both a company car and a season ticket loan (a Londonism which those from elsewhere may not know). The secretarial staff all commuted. Many lived down the GE/LT&S lines, almost all beyond London. We had a secretarial Temp who commuted all the way from Reading on the 1980s coach service into the City, sometimes 2 hours each way, but cheaper than rail.