docs(self-hosted): differences between SaaS and self-hosted

Closes getsentry/self-hosted#3314

develop-docs/self-hosted/index.mdx

@@ -9,6 +9,18 @@ For the sake of simplicity and ubiquity, we have chosen to use [Docker](https:/
 
 If you're self-hosting Sentry and want to know how to switch to Sentry SaaS, check out this [live workshop](https://sentry.io/resources/migrate-to-sentry-saas-workshop/) to learn more about our relocation tooling.
 
+### Differences between self-hosted and SaaS
+
+The difference only resides on a few things that are impossible to be hosted by most people and billing/payment-related. These are some of the things that are not available on self-hosted (due to previous reasons):
+
+- Pricing tiers & Billing system.
+- [Spike protection](https://docs.sentry.io/pricing/quotas/spike-protection/), as it is tightly coupled with Billing Quotas.
+- [Spend Allocation](https://docs.sentry.io/pricing/quotas/spend-allocation/), as it is tightly coupled with Billing Quotas.
+- AI & ML features (such as autofix), although the code is open at [getsentry/seer](https://github.com/getsentry/seer).
+- [Data Storage Location](https://docs.sentry.io/organization/data-storage-location/), because you own your data.
+
+To put things simply, consider self-hosted as the Business plan without any software limitations and no paid tier.
+
 ## Getting Started
 
 Our recommendation is to download the [latest release of the self-hosted repository](https://github.com/getsentry/self-hosted/releases/latest), and then run `./install.sh` inside this directory. This script will take care of all the things you need to get started, including a base-line configuration, and then will tell you to run `docker compose up -d` to start Sentry. Sentry binds to port `9000` by default. You should be able to reach the login page at [http://127.0.0.1:9000](http://127.0.0.1:9000/).