Yeah I get it, I work for a similar company for my day job. My day job is also enterprise storage administrator for this company.
However
- cost - you need to compare like for like. most who come out with the lower cost for on-prem aren't comparing like for like. they aren't counting access from anywhere, storage management, capital expenditure, etc.
- security - this will change as more realise that on-prem security when enabling remote work is not as simple as they think it is.
- speed - this is what your local SSD is for - as a local cache that you can sync somewhere else and work with the local copy which is transparently synchronized. Broadband speeds are approaching the speed of local off-device storage as well now. We aren't there yet, but it isn't inconceivable to see this inside 10 years vs. bulk (hard drive based) storage.
The TLDR is that most are not calculating the costs of like for like (comparing local hard drives to enterprise arrays, etc.) and massively over-estimating how secure they are.
Sure icloud has had some hiccups but those are implementation hiccups, not problems with the concept. If you're not comfortable with it, get some storage in 365. triple redundant across multiple datacenters, provides litigation hold for esentially infinite retention of certain content if required, etc.
As to subscription cost for storage vs. on prem - it makes it a lot easier to get either temporary storage or incremental upgrades vs. an on-prem san. Need 1-5 more terabytes than your SAN has available in the same storage blob? New disk shelf time!
Need an incremental upgrade for a week/month/whatever via cloud? just add what you need and pay a small incremental cost.