> Frameworks like Rails come with a constant upgrade overhead cost. If you're a solo developer, or even a small (<5) team, that overhead is likely to dominate your development time.

Many years ago I used to write projects with Python/Django. The Django project releases 3-year LTS versions with 3-month overlap. LTS versions are supposed to ease the constant upgrade overhead, and hitting a 3 month window every 3 years doesn't seem too bad, especially when they also release documentation specifically guiding you from one LTS version to the next. Does Ruby/Rails not do this?