You probably aren't renting further out. Owning a place versus just renting it changes the calculus quite a bit, and you are coming out ahead compared to paying 25% more to live closer in. Working from home also makes a huge difference. A longer commute is tolerable if you only have to do it a few times a week. The days where you don't commute add up to pay rise.
The problem is everyone else realises this too. Pricing in the south east of England is based around proximity to London commuter lines. You can go a huge distance to Southampton and you're still paying a large premium on housing because it's on an express line to London. Or the tiny town of Fleet which is in Hartley Whitney but has some of the highest prices and desirability in the country, again it's on an express train route to London. Ticket pricing works by marking up prices on these commuter routes to London and using those to subsidise the rest of the customers. The model somewhat falls apart as the wealthier commuters were far more likely to be in jobs that moved to flexitime/remote hence the scramble for revenue now post pandemic.
To answer your point to "live further out" as in actually pay enough for housing that it covers the ticket costs you're talking about Birmingham and beyond hour commutes.