you can have conduit, there is an oval one that will (just) fit under plaster.
However, if you house had been rewired with conduit fifty years ago, even though the copper and PVC are in fine condition, you would now want four times as many sockets, new circuits for the cooker, a dedicated circuit for the kitchen and/or utility room, separated circuits for each floor of the house, lights and switches in different places, so a lot of the conduit would not go where you needed it.
old metal conduit (from the 1920 and 30's, say) was available in two grades, and the cheaper one is not now considered satisfactory because it does not have good joints that will enable it to be dependably earthed.
I have worked on buildings that were wired in about 1970, and the cable has been in good condition except that some batches were made using a chemical in the PVC that reacts with copper, and needs to be removed.
PVC cable has a life longer than you do, except when it is exposed to sunlight outdoors, or stupidly installed in hot conditions, such as touching hot pipes, or touching polystyrene. So it doesn't "need" to be renewed every 25 years.
I still recommend conduit in kitchens, where you can run it all round the room 150mm above worktop level, with hundreds of sockets and switches, and it can be cut into to add more in the same row.