Berenice
I doubt that the British ever restricted the erection of memorials by the Boers. 'Conciliation' and 'nation building' were the orders of the day after the war ended. If there were delays in erecting such memorials, the reason is likely to have been financial rather than political. The war took a heavy toll on the economy of the defeated Boer Republics and the Boers had far more pressing needs for their money.
Certainly in Natal there were indications that re-establishing harmony between Boer and Brit followed soon after the war ended. Elsewhere in this forum I wrote about the Natal Government's campaign to stop the award of the QSA to black soldiers. One of the excuses given was that the medals would be worn to deliberately annoy/upset local Boers. At about the same time, there was an article in the Natal Police magazine, 'The Nongqai', in which the names were omitted of Boers suspected of looting the farms of English-speaking Natalians. This was done in order to avoid re-igniting ill-feeling towards individual Boers.
Regards
Brett