[bmoxb]

I can say for certain of course, but I would guess at that being the result of the poor service that travel network providers typically offer. I have also used travel eSIMs in Japan and had generally a pretty poor experience (bad coverage and slow speeds). Conversely, I've had non-travel, regular monthly eSIM contracts in both the UK and Germany and experienced few issues (at least no more than my experience with physical SIM cards).