Will there ever be a native ARM installer for it and if so when?
Likely with the next version of Lazarus.
For the native "stable" version there's a need in a "stable" FPC release with the official M1 support.
AFAIK, the official FPC releases don't support M1, but the trunk and the "fixes" branches do.
As
trev mentioned in the previous post, you can build your own version from sources.