The perception of LTK as a 'failure' and Dalton as another 'George Lazenby' didn't come about until GoldenEye's publicity machine got into operation. Indeed most reviews of the LTK at the time of its release applauded its tougher approach and Dalton's performance. Certainly in all the years between LTK and GE there was no obvious nastiness about it. Only when GE showed up did people start bitching up Dalton.
Perhaps in the UK. However here in the US the public were unfortunately less willing to even give Dalton a chance, which is why the film basically bombed here in the US.
The thing I don't understand in this context is, LTK wasn't Dalton's first film; that honour goes to TLD, which apparently did well enough also in the USA to justify LTK being shot. If the US public hadn't been willing to give Dalton a chance, wouldn't they have kept away from TLD in the first place?