301 redirecting for an expired domain can be beneficial in some cases, if you can do it properly. Otherwise you have to face some negative aspects also.
Positive Side:
Link Authority: If it has quality backlinks, some SEO values or ranking powers can be transferred.
Traffic Retention: Traffic of old domain can be transferred to new site.
SEO Boost: If it is relevant, you will get some SEO benefits
Negative Side:
Relevance Issue: Cons: If the domain has a completely different content, Google can take it negatively.
Risk of Penalty: If the domain is spammy or penalized, it can be damaged.
Link Juice Loss: Not all backlink value is transferred in a 301 redirect.
Finally, If you can do it properly, you can have benefits otherwise, it can hamper SEO.