The supplied material does not establish that a WIRED author contacted more than 100 companies and received deletion notices instead of personal-data disclosures; the closest sources discuss related privacy problems but do not document those specific events.
After requesting his personal data from more than 100 companies, the WIRED author received deletion notices from some of those companies instead of the requested data.

Companies are hoarding personal data about you. Here’s how to get them to delete it.
Source: washingtonpost.com
Key Evidence
The excerpts do not document a WIRED author contacting more than 100 companies or receiving deletion notices instead of the requested data.
The Markup and KPBS sources report that companies made data-deletion requests more difficult, which is relevant background but not confirmation of the specific claim.
The closest WIRED result concerns a personal-data-removal service and warns that submitting information to more companies can itself expose those companies to the data, but the excerpt does not report the alleged deletion notices.
What the Evidence Shows
None of the supplied sources directly verifies the claim’s central details: the identity of the WIRED author, requests sent to more than 100 companies, or deletion notices being returned in place of the requested data. The search extracts identify broader difficulties with obtaining or deleting personal information, but they do not report the alleged experiment or its results.washingtonpost.comwashingtonpost.comCompanies are hoarding personal data about you. Here’s how to get them to delete...
wired.comwired.comI Tried DeleteMe, a Service That Removes Your Personal Info From the Internet+1 more
The Markup and KPBS reports provide related context. They describe companies making data-deletion requests harder, including technical barriers and privacy instructions that may complicate the process. That evidence supports the general proposition that companies can mishandle or obstruct privacy requests, but it does not confirm that companies responding to a WIRED author substituted deletion notices for data-access responses.themarkup.orgthemarkup.orgWe caught companies making it harder to delete your personal data online
kpbs.orgkpbs.orgYou have a right to delete your data. Some companies are making it extra...
The remaining material is either about data brokers hiding opt-out pages, an individual Hacker News account, legal exceptions to deletion rights, or general guidance from a data-removal service. Those sources cannot independently establish the specific WIRED account, and some are secondary or user-generated material rather than original reporting or company records.wired.comwired.comData Brokers Are Hiding Their Opt-Out Pages From Google Search
lawwwing.comlawwwing.comWhat to do when a customer requests data deletion?+3 more
The claim may refer to a WIRED article not captured in the excerpts, but the provided evidence is insufficient to verify it. On this record, the broader privacy issue is documented, while the precise numerical and procedural details remain unconfirmed.