Is it not somewhat incredible that a new railway does not have the capacity to accomodate cyclists at all times?
In the context of London region commuter services, it is just not practical, short of major network capacity improvements. While there has been a small drop in peak passengers compared with pre-covid, it is not enough of a drop to leave sufficient space on trains to accommodate a substantial number of cycles at peak hours. There are also the problems of platform capacity and station dwell times. A lot of passengers with cycles would take up a lot of platform space and would be a hazard, especially at stations without step-free access if it meant a number of people carrying bikes up or down busy stairways. Having a number of passengers with cycles boarding or alighting (or both at the same door!) would affect dwell times and therefore reliability and so the number of trains which could use the line per hour.
Part of the issue is that demand for cycle carriage is too high to meet with any currently practical measures, but too low to support really innovative solutions such as dedicated Motorail-like 'pedalorail' trains, aimed mainly at carrying commuter cyclists and their machines. Such trains could in theory run from fairly quite outer-suburban origins where there was time and room to load them to destinations on the fringe of the city centre as opposed to the big termini, from where the commuters dispersed to their final destinations. The issues with that are three: probably not enough demand to justify them, not enough capacity for the additional trains, and no remaining quiet stations on the centre fringe. If Kensington Olympia still handled about eight trains per day as it once did, then a peak-hour 'pedalorail' service from places like all stops from Shepperton to Teddington, or from Hampton Court, Thames Ditton and Berrylands, then non-stop to Olympia might have had a role if the paths and vehicles were available. (But perhaps this really belongs in the 'Speculative discussion' thread).