Every year, the Jingū Taima, the ofuda from Jingū that the Shinto establishment would like every household in Japan to venerate, are distributed to jinja across Japan so that they can be handed on to individuals. However, the ofuda are not just posted to the jinja. There are a number of ceremonies involved in the distribution itself.
The first takes place at Jingū in September, and is attended by representatives of Jinja Honchō, including the president and chairman, as well as by the priests of Jingū. At this ceremony, the ofuda are placed before the kami, along with offerings, and the lesser chief priest of Jingū recites a norito. The priests then offer a tamagushi and reverence in the standard form for priests of Jingū, which involves eight bows, followed by the chairman of Jinja Honchō offering a tamagushi, and all the representatives offering a standard reverence. The ofuda and offerings are then removed from before the kami, and the greater chief priest of Jingū gives the ofuda (one, symbolising the rest, on a sanbō stand) to the chairman of Jinja Honchō.
The priests then withdraw, and the top officials of Jinja Honchō distribute symbolic Jingū Taima to the heads of the 47 prefectural Jinjachō.
This ceremony is reported every year in Jinja Shinpō, but the following ceremonies are not reported as reliably, because there are a lot of them, so I am putting the details together from memory of a lot of separate reports.
First, the prefectural Jinjachō have another gathering and ceremony, at which the ofuda are distributed to the heads of the local groups (“shibu”, in Japanese). These local groups are the lowest level of formal organisation; for example, Kawasaki has a single local group. Each local group, I think, then holds its own ceremony, at which the ofuda are distributed to representatives of each individual jinja in the area.
This should make it clear why Jinja Honchō sees problems with simply posting ofuda to people overseas who want to practise Shinto. To get Jingū Taima to local jinja for appropriate distribution, there are three ceremonies, at the last of which the ofuda are handed over to the people who will, personally, hand them over to the people who want to venerate them. In other words, in theory the Jingū Taima are always passed directly from one person to another in a Shinto ceremony that takes place in a sacred space. If ofuda are posted overseas, then the chain is broken even in theory. I do think that Jinja Honchō needs to find a way around this issue, but there is a real problem here, not just simple resistance to change.
Indeed, change to the detail is not necessarily resisted. The first Jinja Shinpō of this year reported on one of the local group ceremonies, held in Shiga Prefecture, just north of Kyoto, at the end of October. This ceremony was conducted entirely by female priests, for the first time in that prefecture, at least. A quarter of the priests (seven out of 28) in the local group are female, which is quite high, and probably part of the reason. The head of the local group, who is not female as far as I can tell from the name, said “Although this is unprecedented, now that we are in the Reiwa Era it is a good opportunity for us priests to also try new things”.
Because this ceremony is attended by the sōdai (senior parishioners) of most, if not all, jinja in the group’s area, one reason may have been to get them used to the idea of female priests, and make it clear that the establishment regards them as fully equal to male priests. Whatever the specific motivation in this case, it does show that the Shinto establishment is happy with the idea of making changes within the process, as long as they do not undermine the fundamental reasons, and so there is reason to hope that they will work something out for people overseas.