I can understand £50k being ' not enough' yet not living in any way a 'good life with plenty of cash spare'
As an example 2 years ago we had two children in childcare:
Nursery £80 per child, per day. £400 each per week (£800 for two), = £3200 per month for full time London childcare for two.
Our rent on one bed flat is £1750 a month.
= £4950 just on accomadation and childcare. That's without food and bills and anything else
Lucky for us we didn't need both children in childcare full time so paid less as less days/ hours. But that's what the fees were and many at the nursery did need full time childcare
To afford almost £5000 a month in just childcare and a one bed flat you would need a take home pay of £60,000 after tax ( around £90,000 annual before tax) Of course you also need to pay bills and eat, and children clothed etc. So that's £100,000 easily to live a lifestyle of two parents working full time, full time childcare, and a small flat, plus bills and food