Why are there no planetary occultations visible from Earth between 1818 and 2065, when otherwise they are comparably frequent?

The orbits of all the planets are in a slightly different plane, so planetary occultations are rare events. The Earth and two other planets must be in a line for an occultation to occur.

Two planets occultating twice with a relatively short interval between them is a common pattern in occultations; these pairs of occultations don't recur for centuries.

The interval 1818-2065 had no occultations because there are long intervals between occultations of any pair of planets this interval was between events. There will be future periods of similar length with no events. Some centuries, like the 1700s and 2000s, have four or more occultations. Other centuries, like the 1900s, have none.

It's interesting to note that the Venus and Jupiter occultation in 2065 won't be seen because it happens too close to the sun to be seen.

Because of the unique orbital dynamics and inclinations of the planets and the Moon during that time, there are no planetary occultations visible from Earth during this period because the planets' and the Moon's orbits do not align in a way that would allow for observable occultations.