Again, why would one need such a heavyweight tool?

Most frameworks have powerful loggers out of the box, like Monolog in the PHP world.

What specifically is heavyweight about OTEL? At its core it's a standard for producing structured logs along with some standards for exporting/collection. The heaviness is really implementation-specific and can vary stack to stack

There's even a handler for monolog in PHP - they are not necessarily mutually exclusive

https://github.com/open-telemetry/opentelemetry-php/blob/mai...

Yes but instead of just logging to a text file for example you need OTEL, thats my point.

The fact that Monolog has a handler for this tool isnt relevant, but it shows that there is one more layer of complexity tacked on.

That doesn't really mean it's heavyweight though; an extra layer, sure (but I don't even really agree that it's complex - you set it up once and then mostly just log the same way you would with any other).

You can still log to a text file if you want to run locally, but for something like next.js where you're intended to deploy production to some cloud somewhere (probably serverless) the option of _just_ writing to a text file doesn't really exist. So having OTEL as an ootb supported way to do o11y is much better than the alternative of getting sucked into some vendor-specific garbage like datadog or newrelic