Evidence from 2024 and early 2025 shows that the core of Jason’s prediction—continued sluggish smartphone and premium-smartphone sales in 2024—did not materialize at the market level, even though some details (like long upgrade cycles and flat iPhone revenue) were directionally right.

Key points:

1. Global smartphone unit sales rebounded in 2024, rather than remaining sluggish.
   IDC reports worldwide smartphone shipments reached about 1.24 billion units in 2024, up 6.4% year‑over‑year, marking a strong recovery after two years of decline and six consecutive quarters of shipment growth. (businesswire.com) This is inconsistent with a continued "major slowdown" or broadly "sluggish" unit sales in 2024.

2. Premium smartphones grew faster than the overall market instead of seeing flattened/weak revenue growth.
   Counterpoint Research finds the premium segment (≥$600) grew about 8% YoY in 2024, outpacing overall smartphone market growth (~5–6%), and its share rose to 25% of the global market, a record high, with OEMs explicitly “focusing on revenue over volume.” (counterpointresearch.com) That indicates robust, not flat or weakening, revenue growth for premium smartphones overall.

3. Apple’s own iPhone business was flat, but that’s the exception, not the whole premium market.
   Apple’s FY 2024 Form 10‑K shows iPhone net sales of $201.2B in 2024 vs. $200.6B in 2023, and Apple explicitly describes iPhone net sales as “relatively flat” year‑over‑year. (sec.gov) IDC’s shipment data similarly show Apple’s 2024 smartphone shipments down about 0.9% YoY (232.1M vs. 234.3M). (businesswire.com) This does match his claim that high‑end makers like Apple would see muted growth—but the prediction was framed as a broader, global premium‑smartphone slowdown, which did not occur.

4. Upgrade/refresh cycles did continue to lengthen, but this did not prevent a 2024 rebound.
   IDC notes that even as refresh cycles continue getting longer and the used‑phone market grows, 2024 still brought a solid shipment rebound driven by pent‑up upgrade demand. (itnewsonline.com) Consumer reporting in 2025 also emphasizes that Western users now tend to upgrade roughly every four years instead of two, clearly indicating people are skipping multiple generations. (thetimes.co.uk) So the “people will skip 2–3 versions” / long‑cycle part was accurate, but it did not translate into the broad, continued slump he forecast for 2024.

Putting it together:

• Correct: upgrade cycles lengthened and Apple’s iPhone revenue was basically flat.
• Incorrect at market level: 2024 did not continue a “major slowdown” in smartphone unit sales, and premium‑smartphone revenue growth accelerated above the market rather than flattening or weakening.

Because the central thrust of the prediction was that 2024 would be another year of sluggish smartphone and premium‑smartphone performance globally—and the actual data show a clear rebound and strong premium growth—the prediction as stated is best judged wrong overall.