Bouygues SA is a diversified French conglomerate with significant asset base and substantial leverage reduction in 2023 vs 2022, high cash generation from contracts, and a complex capital structure. Key observations from the data:
- The group has large scale assets and substantial cash flows, with Revenue and EBIT contributing to stable cash generation, though it carries meaningful long-term and current borrowings, lease liabilities, and net debt improvements (Net Debt 2023: €7.44bn vs 2022: €0.94bn? Note: Net Debt rose meaningfully; however overall liquidity indicators show sizable cash and controlled operations).
- It is not a pure regulated utility; Bouygues operates in construction/construction materials/media/telecom via Colas, Bouygues Telecom, and Bouygues Construction. This is a diversified industrial with cyclical exposure, not a classic regulated utility.
- S&P-like framework suggests tech for calculations; but no explicit rating provided. However, the company’s cash flows depend on construction cycles and market demand; not a straightforward low-volatility regulated cash-flow profile.
- Hybrid bonds are typically more attractive for regulated/infrastructure or utilities with stable, predictable cash flows and investment-grade profile. Bouygues seems more cyclical with exposure to construction cycles, albeit large scale and diversified; the measure of FFO/debt and leverage headroom would be important; given high long-term borrowings and current liabilities, there is some debt maturity risk, but cash flow from operations seems sizable (Cash Flows From Used In Operating Activities: 2.978b in 2022). However, net debt position increased significantly in 2023.

Given the guidelines:
- Not a regulated utility or infrastructure-like core business; more mixed, with moderate but not guaranteed cash-flow visibility.
- Hybrid issuance would be opportunistic rather than core funding; it could provide some leverage headroom but not a robust core use-case.
- Market data (swap curves, corporate bond indices) show reasonable spreads but no clear rating or rating headroom. Without a sure upgrade path or stable regulatory regime, the case for “Strongly Suitable” would be weak.
- Bouygues’ status as investment-grade (assumptive) could be considered, but we don’t have explicit BBB+ status; even if IG, the company is not a pure utility; thus hybrid as a substitute for equity would be riskier.

Conclusion: Marginally Suitable. Explanation: moderate cash flow visibility but not core regulated/infrastructure business; hybrid could be used opportunistically to optimize capital structure, but not a primary funding instrument; benefits to rating headroom exist but are not guaranteed; investor appetite and pricing risk due to cyclicality and complexity. Therefore: Marginally Suitable.

<answer>Marginally Suitable</answer>