People are already scanning npm constantly. You can limit yourself to pre-scanned packages by setting npm's minimum release age setting to 1 or 2 days (a timeframe that all the recent high-profile malicious package versions were unpublished within).

If it runs in a harness that will alert me when something dodgy is detected I'm fine to stay at that level.

I don't read it in detail because reading in detail is precisely what I delegate to the harness. The alternative is that I delegate all this trust to package managers and the maintainers which quite clearly is a bad idea.

Whether the $$ pricetag is worth it is.. relative. Also in Go you don't update all that often, really when something either breaks or there is a legitimate security reason to do so, which in deep systems software is quite infrequent.

Funnily enough for frontend NPM code our policy was to never ever upgrade and run with locked dependencies, running few years old JS deps. For internal dashboards it was perfectly fine, never missed a feature and never had a supply chain close call.

It is the default in both cargo and npm, but "npm install" stupidly enough still updates the lockfile, and you need "npm ci" to actually respect it. I think there's some flag to make install work sanely, but long-term I find the best approach is to use anything other than npm.

I ditched npm for yarn years ago because it had saner dependency resolution (npm's peer dependency algorithm was a constantly moving target), and now I've switched from yarn to bun because it doesn't run hooks in dependencies by default. It also helps that it installs dependencies 10x faster.