When does a gas boiler need to be replaced?

Hello everyone,
I received a house "as a gift" last spring. That means I have been the owner since 2018.

The house has a gas heating system installed. The gas boiler is a Vaillant VKS 23/1E (natural gas) from 1990. Maintenance has been performed every year so far and the values are fine. Likewise, the district chimney sweep found no defects.

Is it true for this boiler that it must be replaced after 30 years, even if all values are still perfect and no major repairs have occurred so far?

As an addition:

Quote from BMWI Efficiency Class Calculator

KS 23/1 E
Manufacturer:

Vaillant Deutschland GmbH & Co. KG

Year of manufacture:

1990

Nominal output:

23 kW

Fuel:

Gas

Boiler group:

Low-temperature boiler

Boiler type:

Atmospheric gas heating boiler

Pilot flame:

No

Efficiency value:

73 %

Efficiency class:

D

Marking from (exact regulation see §16 and §17 EnVKG):

by authorized persons (e.g. heating installers, chimney sweeps, building energy consultants): 2017

by obligated persons (district chimney sweep): 2017

There is no mention of a replacement obligation according to §10 Energy Saving Ordinance

In §10 Energy Saving Ordinance it says:
(1) Owners of buildings may no longer operate boilers that are fueled with liquid or gaseous fuels and that were installed or set up before October 1, 1978. Owners of buildings may no longer operate boilers that are fueled with liquid or gaseous fuels and that were installed or set up before January 1, 1985, starting in 2015. Owners of buildings may no longer operate boilers that are fueled with liquid or gaseous fuels and that were installed or set up after January 1, 1985, after a period of 30 years. Sentences 1 to 3 do not apply if the existing boilers are low-temperature boilers or condensing boilers, as well as to heating systems whose nominal output is less than four kilowatts or more than 400 kilowatts, and to boilers according to § 13 paragraph 3 numbers 2 to 4.

So I understand it to mean that only constant temperature boilers, even in the case of a change of ownership after 2002, must be replaced and low-temperature boilers do not.

Is that correct?

Replace it only if it is not repairable, not before.

Your district chimney sweep will be able to tell you.