Yes and no.

Yes. The incentives for writing reliable, robust code were much higher. The internet existed so you could, in theory, get a patch out for people to download - but a sizeable part of any user base might have limited access, so would require something physical shipped to them (a floppy or CD). Making sure that your code worked and worked well at time of shipping was important. Large corporate customers were not going to appreciate having to distribute an update across their tens of thousands of machines.

No. The world wasn't as connected as it is today, which meant that the attack surface to reasonably consider was much smaller. A lot of the issues that we had back then were due to designs and implementations that assumed a closed system overall - but often allowed very open interoperability between components (programs or machines) within the system. For example, Outlook was automatable, so that it could be part of larger systems and send mail in an automated way. This makes sense within an individual organisation's "system", but isn't wise at a global level. Email worms ran rampant until Microsoft was forced to reduce that functionality via patches, which were costly for their customers to apply. It damaged their reputation considerably.

An extreme version of this was openness was SQL Slammer - a worm which attacked SQL Servers and development machines. Imagine that - enough organisations had their SQL Servers or developer machines directly accessible that an actual worm could thrive on a relational database system. Which is mindboggling to think about these days, but it really happened - see https://en.wikipedia.org/wiki/SQL_Slammer for details.

I wouldn't say that the evidence points to software being better in the way that we would think of "better" today. I'd say that the environment it had to exist in was simpler, and that the costs of shipping & updating were higher - so it made more sense to spend time creating robust software. Also nobody was thinking about the possible misuse or abuse of their software except in very limited ways. These days we have to protect against much more ingenious use & abuse of programs.

Furthermore today patching is quick and easy (by historical comparison), and a company might even be offering its own hosted solution, which makes the cost of patching very low for them. In such an environment it can seem more reasonable to focus on shipping features quickly over shipping robust code slowly. I'd argue that's a mistake, but a lot of software development managers disagree with me, and their pay packet often depends on that view, so they're not going to change their minds any time soon.

In a way this is best viewed as the third age of computing. The first was the mainframe age - centralised computer usage, with controlled access and oversight, so mistakes were costly but could be quickly recovered from. The second was the desktop PC age - distributed computer usage, with less access control, so mistakes were often less costly but recovering from them was potentially very expensive. The third is the cloud & device age, with a mix of centralised and distributed computer use, a mix of access control, and potentially much lower costs of recovery. In this third age if you make the wrong decisions on what to prioritise (robustness vs speed of shipping), it can be the worst of both the previous ages. But it doesn't have to be.

I hope that makes sense, and is a useful perspective for you.