On the contrary, Boris got considerable leeway from the public over the difficult decisions he had to make around COVID, both the stuff that was understandable

On the contrary, Boris got considerable leeway from the public over the difficult decisions he had to make around COVID, both the stuff that was understandable but flawed like delaying certain decisions and the arbitrariness of some of the implementation to the decisions that were staggeringly inept (reopening schools for one day in January 2021, thereby maximising educational disruption and the opportunity for COVID spread) because his government got one big thing right (accelerated vaccination programme) and was more generous than people expected in providing benefits. Even now his government polls well in COVID handling. His Brexit deal which delivers few of the promises he made and even he insists needs renegotiating is popular with people that voted for Brexit too. The public would probably have shrugged off him seeing the cost of living crisis as a good time to push a flat tax (NI) increase were it not for the issue of lockdown parties he attended and continues to insist didn't break any rules because of the special nature of his home/workplace and staff: which ultimately is the exact same populist dynamic "the politicians think they're better than you" he rode to power. I agree it'll be hard for an immediate successor to recover in the polls, but it was populist anger at his personal behaviour (and related self-inflicted wounds like responding to his MP being censured by the committee that investigates Parliamentary standards by throwing out the committee) that saw him and his government nosedive in the polls in the days that immediately followed the revelations and his reaction, not the difficulty of navigating COVID for the last couple of years.