I not
That is a fair point of course, but even now at nearly 8pm pax at Basingstoke for Pompey/So’ton/Bomo/Weymouth are being directed onto Yeovil/Exeter services for a journey via Salisbury. That will, of course, be via either a two car SWR 158 or the already very well loaded GWR services, changing once again at So’ton for anywhere in the New Forest or beyond.
If the combined wit of the modern railway honestly cannot manage a Portsmouth/Weymouth - Basingstoke shuttle, this late in the day and given the sheer volume of crew and stock not currently being utilised on their diagrammed services, then the situation needs a serious looking at. It may or may not be the fault of any one particular organisation, but it’s poor.