OK - they have ruled 63 out of 67 years . Not bad , ey ?
They were also out of power for three years in the 1990s. Two of the three parties that were in power then don’t exist anymore. The other one was the Socialists (now the Social Democrats). One advantage the LDP has is that it’s been around as long as it has. The other parties are always forming and reforming and changing their names.
As long as the elections are legit, why not.
Perhaps the Japanese don’t like the socialism of the other parties that much.