Yes, by doing this over the years it seems that you have massively underreported taxable income. Given the large amount of underreporting each year, it's likely that the statute of limitations for the IRS to assess taxes is extended to 6 years (separately for each year that you did this).
Another way to state the limitation is that sum of the amounts with codes D, E, F, S, AA or BB from all of your 2023 Forms W-2 is not permitted to exceed $30,000 for someone age 50 or over in 2023.
The $73,500 limit is a per-plan limit (defined in section 415(c) of the tax code) for someone age 50 or over, not an individual's limit, but that includes employer contributions. The individual's employee deferral limit is as we have described and is a combined limit (defined in section 402(g) of the tax code) that applies to the individual across all of the 401(k), 403(b), federal TSP, SIMPLE and SARSEP plans in which the individual participates.
I'm not going to comment on how to go about addressing such a large, multi-year error. It might make sense to consult with a tax attorney.
