Not convinced your comment explains Reform picking up so much while Cons remains steady. Very plausible over Labour, Lib Dem and Green.

Johnson's hero Pericles (an extravagant builder) was dismissed from office in 430 but restored in 429 to die of plague. Thucydides considered eventual defeat of Athens in 404 due to abandonment of Pericles strategy. Johnson visibly hoping for same write up over destruction of Conservatives Party

The increase in Reform is considerable and potentially important. The small increase in Green may also be significant. There may be more churning underneath - eg Lab to Cons and Cons to Reform which matters long term.

Until the 1960s Schedule A Income Tax was charged on the imputed value of occupation based on estimated rent. Mortgage interest was deducted from Income. So today Schedule A would bring in at least 1 per cent of GDP and massively shift the tax burden

This graph does not show the complete picture of tax and GDP. Local authority rates were very substantial compared to central govt revenue for the Edwardian era.