Anytime your cloud spend with a single vendor starts to get out of hand, you just call and negotiate. If you make a multi-year commitment, they'll apply a substantial discount. Also, $100k/yr is still cheap compared to the cost of developers. Not just in terms of actual price tag, but risk management because a SaaS won't quit for a better offer.
If you need to hire 1 more developer at $100k to help maintain your data warehouse or pay $100k for Snowflake or BQ, its a no-brainer to use SaaS.
Also humans cost more than their salary: Recruiting, management, benefits, attrition, vacation, the risk that they are just not capable.
A human will also cost you more year over year (raises, promotions, etc), SaaS will typically cost you less year over year (optimizations, negotiations, competition, etc).
