I think in a situation like this there are two ways to define "safe".
Is the dividend safe based on actual cash flow and earnings numbers? No. The company is going on its third straight year of not being able to cover the dividend. The last time this happened was almost twenty years ago. The reason the stock is drawing down so heavily right now is primarily related to guidance. The company was expected to generate enough free cash flow on the year to cover the dividend in 2024 but cash flow expectations actually came in below last years numbers and it is currently sitting on a 20%~ shortfall in terms of free cash flow when it comes to dividend coverage.
On the other hand, do I believe that BCE will do anything they can to not cut the dividend? Yes. So, I would view it as "safe" in that regard. However, this isn't exactly the best situation for shareholders over the long-term. When a company cannot cover the dividend and they want to maintain it, they must do so by issuing debt, equity, etc. Neither of which are good for shareholders over the long term. Although it is painful to think about, a dividend cut by BCE would be better for shareholders over the long-term, unless we see some significant turnaround in its operations.
I think it is important we understand that yield doesn't equal return when it comes to dividend investing. A lot of people get caught up in this mentality. There is really no point to owning a 8% yielding stock that is losing 10% in price a year.
Do I think the dividend will be cut? No. Is the dividend safe? Underlying numbers say no.
Hope this helps!