Is it me or is it OTT for someone in their late 20’s on an average income to be regularly investing into a S&S ISA with the intention of this not being accessed until their 50’s? They probably have a spare £7/800 to save at the end of each month and regularly put about £350 of this into this ISA. For context - 1 child and own house with a Mortgage.
Edited to say he has a workplace pension too.